Mini White Cakes + Citrus Curd + Mousseline Buttercream

My sister is coming from Virginia with her oldest daughter in a couple of days.  They used to be California types like us, but life’s necessities took her family to the East Coast for a few years before they were able to return to the Golden State, and then, opportunities not available here saw them back in Virginia.  Forever.  We stay in touch on Facebook, with occasional emails, and like a few mornings, ago phone calls from the grocery store while she was looking for cake flour.   My lovely, svelte sister is not a baker.  Lucky woman.

I miss her quite a bit these days, wondering if I’m suffering from the realization of not having taken advantage of her being closer when she was here.  There were quite a few years when she and I were each raising a house full of children and like most families, found time to get together for barbeques on birthdays and holidays, but we both had careers, so life was quite busy then.  I have three boys, and she, three girls.  She wanted a boy, and I a girl, but that wasn’t what happened, so I always thought I might get my fix of girls from spending time with hers — as in have sleep overs.  Tea parties.  Dressing up and painting toenails lots of crazy colors.  I guess one of my biggest flaws is idealism.  Silly me.  One can’t exactly have a tea party unless one invites a few tea party goers, can one?

Her youngest daughter– the last of our six boys and girls — is just finishing high school and so both my sister and I are facing very different times in our lives.  Mine has been focused on learning to live in a very quiet house newly void of boys since seeing my youngest off to college this past fall.  She is preparing for a wedding — her oldest daughter is to be married this coming summer.

As much as I missed many chances to get to know her daughters better than I have over the years, I was pleasantly surprised — humbled actually — to have my bride-to-be niece call late last year and ask if I might consider making her wedding cake.


Sure, I’ve made cakes.  Lots of them. But I’ve never made a wedding cake.


I’ve never made anything with fondant, either, choosing instead to watch from afar as others work wonders with it.

The cake is to be round, not square.  Three-tiers of lemon with vanilla buttercream for 100 guests.  White fondant with varied shades of  yellow teardrops cascading down the sides.  Clean, sleek, simple.

And I have to figure out how to get it to L.A. where the wedding will be held.

Thankfully, I have many baking friends willing to share their experiences with fondant with me, as well as other great resources I’ve been learning from.  I’ve also buried myself in my favorite cake book, Rose Levy Beranbaum’s The Cake Bible.  I enjoy it because of the way the recipes are organized including both weight and volume in the ingredients list.

Since we’ve had an amazing variety of citrus to enjoy this winter, I decided to use that to begin my first experiments in wedding cake baking.  Three types of citrus curd and buttercream filling six little square cakes covered with a reasonably edible fondant may seem a bit over zealous for a first attempt, but I have a tendency to be that way in general.  It pushes my thinking while I make an enormous mess in my kitchen.

My next practice session begins today so my niece and sister can sample the flavors when they arrive, then I’ll make necessary adjustments and practice a few more times before the real cake is baked in July.

Wish me luck, and by all means, if you’ve done this before and have any recommendations, I will be more than happy to listen.

33.365 juicy mess (Explored!)

Mini White Velvet Butter Cakes with 3-Citrus Curd and Mousseline Buttercream

For the Meyer lemon curd…

4 lg. egg yolks

1/2 c. + 2 T extra fine sugar

3 oz. freshly squeezed lemon juice

4 T unsalted butter

pinch of kosher salt

2 tsp. lemon zest

For the key lime curd...

4 lg. egg yolks

1/2 c. extra fine sugar (reduced by 2 T compared to lemon recipe)

3 oz. freshly squeezed lime juice

4 T unsalted butter

pinch of kosher salt

2 tsp. lime zest

Use these directions for both the lemon and lime curd: In a medium nonreactive sauce pan, beat the egg yolks and sugar well first, then add all of the remaining ingredients except the zest.  Stirring constantly, cook over medium low heat until it has thickened.  Make sure it does not reach the boil by removing briefly from the heat while stirring quickly each time steam appears, then return to the heat.  The curd will change from a translucent, very pourable mixture at first to something opaque and noticeably yellow on the back of a wooden spoon.  When it’s thickened sufficiently, pour into a stainer and press through the mesh to remove any solid parts.  Add the zest and mix well.  Allow to cool before covering to refrigerate.  The lemon curd will continue to thicken as it cools.  Store up to 3 weeks refrigerated.  Makes 1 cup.

For the blood orange curd…

4 lg. egg yolks

1/2 c. + 2 T extra fine sugar

1 c. freshly squeezed blood orange juice

4 T unsalted butter

pinch of kosher salt

2 tsp. blood orange zest

Reduce the 1 cup of blood orange juice to 1/4 cup either on the stove over high heat or in the microwave on high power and allow to cool.  If you cannot find blood oranges, then use regular oranges, but reduce the 1 cup of juice to 2 tablespoons instead. Proceed with the directions as stated above except add the orange zest to the mixture before cooking, and do not strain after thickened.

Zest and juice the citrus


Lemon and lime curd are made with same steps


All ingredients except zest cook together


The mixture becomes yellow and opaque as it thickens


Lemon and lime curd are strained


The curd will continue to thicken as it cools


Add the zest last to the lemon and lime curds


Orange zest goes in before cooking


Blood orange juice is reduced first before adding to mixture


Three curds ready for use!


Beautiful color...



  • The flavor of each of these curds is incredible, but I enjoyed the key lime most.  The lemon has the brightest flavor and is quite tart.  Beranbaum suggests that should you like it to be more sweet, add sugar gradually while it is still warm.  I found the flavor just perfect.  I was gifted quite a few very ripe Meyer lemons which are by nature more sweet than the more common Eureka lemons, so I was glad to be able to use them for this.
  • The lime curd isn’t bright in color, but its intense flavor makes up for that.  The bits of zest are visible in the finished product.  Quite a refreshing flavor to this.
  • If you’ve not been lucky enough to have sampled blood oranges, they’re quite a bit more tart than regular oranges, or have an acidity level closer to that of lemons and limes.  Since the acidity level is what assists in the thickening of curd, this is important to factor in.  Beranbaum states that if using regular oranges, keep the sugar to just 1/2 c. and expect that the curd will not be a firm as that of the other flavors.


For the White Velvet Butter Cake…

4-1/2 egg whites

1 c. whole milk

2-1/4 tsp. vanilla

3 c. cake flour, sifted

1-1/2 c. extra fine sugar

1 T + 1 tsp. baking powder

1/4 tsp. kosher salt

12 T butter, softened

Preheat your oven to 350 degrees F and position racks in the center to lower third of oven.  Prepare 2-10″ square pans by spraying lightly with oil and dusting lightly with flour.

In a small bowl, mix egg whites, 1/4 c. of the milk and the vanilla.  Set aside.

In the bowl of a standing mixer, combine the dry ingredients by mixing on low for 30 seconds.  Add the softened butter and 3/4 c. of the milk and mix on low until ingredients are blended, then increase speed to medium, beating for about 1-1/2 minutes.  Scrape down the sides of the bowl with a spatula before continuing.

Add the milk and egg mixture to the bowl in three pours, making sure to beat 20 seconds after each addition.  Scrape down the sides before pouring batter into prepared pans.  Bake for 25 to 35 minutes or until a wooden skewer inserted in the center is removed clean.  The surface of the cake should spring back when lightly pressed in the center.

Allow layers to cool in the pan about 10 minutes before removing and cooling completely on baking racks.

Once the layers are completely cool, cut each into 9 small squares.  Trim any crusted edges from the pieces.  Three of these small cake squares will be used to make one mini cake.  You’ll have a total of six mini cakes — two lemon, two lime, and two orange.

To assemble the mini cakes, spread just enough curd on two layers to cover.  Spread buttercream over the curd.  (See recipe for buttercream below.) Ice each of the cakes with buttercream to cover.  Enjoy as is, or cover with marshmallow fondant and decorate.


Bake in square pans


Cut both layers into 9 square pieces



  • Beranbaum’s White Velvet Butter Cake is fabulous.  The flavor is light and delicate, and the texture perfectly moist and tender.  It was wonderful paired with each of the citrus flavored buttercreams.
  • The cake is so tender, I had some problems getting it from one of my pans.  I have a love/hate relationship with my silicone pans.  I like the squares, but their performance always leaves me scratching my head because they don’t seem to perform consistently.  I’ve sprayed, and not sprayed.  Floured and not floured.  Yes, I’ve even lined them with parchment before.  Who knows, but one of the layers stuck in the middle.  I probably should have let it cool longer.  That left me with needing to piece together a couple of the mini cake layers.  Good thing buttercream helps glue things together!
  • All things considered, as delicious as this cake recipe is, I won’t be using it for my niece’s wedding cake because it’s too tender in my opinion.  Perfect for a gorgeous party cake, though.  Absolutely perfect!
  • If you want to make a two layer round, your layers will be thicker, and you can still spread the curd down and then the buttercream.  If you’re adventuresome, split each of the layers and go crazy with the filling, but remember about the delicate nature of the cake.  I’d think about wrapping the layers well after they’re completely cooled, then putting them in the freezer for an hour or so to make handling them easier if you’re planning on splitting them.
  • I know my little cakes look all caddy wompus, but remember I was only making them to sample flavors and textures.  Excuses, excuses for my messy uneven layers!


For the 3-Citrus Mousseline Buttercream…

2 c. unsalted butter, softened but cool

1 c. extra fine sugar

1/4 c. water

5 lg. egg whites

1/2 + 1/8 tsp. cream of tartar

3 oz. Grand Marnier

1/4 c. lemon curd (added separately)

1/4 c. orange curd (added separately

1/2 c. key lime curd (added separately)

In the bowl of a standing mixer beat the softened butter until very creamy, then scrape from the bowl into a container and set aside in a cool place.  Thoroughly wash and dry the mixing bowl making sure to remove all traces of the butter.

Set a large heatproof glass measuring cup near a burner on your stove.  In a small saucepan over medium heat, stir  3/4 c. sugar and the water constantly until the sugar dissolves and begins to bubble.  Turn the heat to low and let it sit.

Meanwhile, beat the egg whites just until they’re foamy.  Add the cream of tartar and continue to beat on high until soft peaks form.  With the motor running at medium speed, add the sugar slowly and beat until stiff peaks form.

Return to the syrup on the stove.  Turn the heat up and boil until it reaches the firm-ball stage (248 – 250 degrees F).  Immediately pour the syrup into the large glass measuring cup you placed next to the burner.  Return to the egg whites in the mixer.  Avoiding the beater, pour a bit of the hot syrup into the egg whites, then turn the motor on high and beat for 5 seconds.  Continue to do this until all the syrup is incorporated into the egg whites.  Make sure to scrape the remaining syrup from the sides of the measuring cup.  Continue beating the egg whites on medium speed until the mixture is absolutely completely cool to the touch, about 2 minutes.  If necessary, reduce speed to low and continue beating until cool.

Now add the butter to the egg white mixture 1 tablespoon at a time on medium speed.  Make sure each tablespoon is completely incorporated before adding the next. Occasionally stop to scrape down the sides of the bowl.  At some point, the buttercream may look as if it has begun to curdle.  Increase speed and mix until it comes together again before adding additional butter.  Lower the speed and add the Grand Marnier.

Divide the mousseline buttercream into three equal portions, about 1-1/3 cup into each of 3 bowls.  Whisk in 1/4 c. lemon curd to one bowl, 1/4 c. orange curd to the second, and 1/2 c. key lime curd to the last.  Mix well and use as described above to fill and the mini cakes.


As you can see, the lemon cake on the right was pieced together after being stuck to the pan.  I’ll have to work on that!


  • This is my favorite buttercream recipe.  It is amazingly sturdy stuff!  Beranbaum states that it can be kept at room temperature for up to 2 days (I’ve kept it at room temp for most of one day), or in the fridge for 10 days.  Although I haven’t made this recipe to work with ahead of time, I plan to.  The directions state that if you do make ahead and store it in the fridge, you must bring it to room temperature before you beat it, or it will break and you will not be able to reform it.  Scary concept indeed!
  • Sorry no photos of this part — I’ve learned the hard way that making this type of buttercream or Italian meringue that it’s better to go without the photos for obvious reasons.  The syrup cools down.
  • This mousseline buttercream is wonderful by itself and the addition of the Grand Marnier or any other liqueur is of course, optional, but will act as a flavor enhancer if you plan to add the curd like I did.
  • If you’re concerned about heating the syrup, it goes much easier than you might think.  I’ve tried beating the egg whites before heating the syrup as well as afterwards, and both work.  It can make a mess in the bowl of your mixer and on your beater if you’re not careful.  For example, one method involves slowly adding the hot syrup while the mixer is running.  Although this works, the air produced by the swirling beater can cause the stream of syrup to be thrown against the side of the bowl.  You have to have a steady hand in the long run.  Clean up isn’t bad if you fill the glass container with water then heat in the microwave to dissolve the sugar.
  • This recipe can be used as I have to fill the layers and to act as a crumb coat before adding a fondant covering.
  • I used the marshmallow fondant recipe found here.  If you haven’t made fondant before, there are some great videos on YouTube like this one which really help make the process in working with it less daunting if you’re a stress cadet about these things like I am.
  • Thanks to John and to Chris of Melecotte for their offers of support.  Much appreciated.
  • If you want to try a non-marshmallow fondant, then Zoe of Zoe Bakes has an excellent rolled fondant tutorial here.  I just may give that version a try as well, since I’m learning, then decide which I’d like to use on my niece’s cake.
  • I only covered three of the cakes with fondant to play around with the feel of it and since these mini cakes weren’t party bound, I sent them off with a friend to be sampled at work.  The plain frosted minis stayed at home for my husband and I to sample.
  • They keep quite nicely in the fridge wrapped in plastic.  Let the buttercream harden in the fridge first before wrapping with plastic.  The flavors intensify as they sit, so this is a great combo to make at least a day ahead.
  • The biggest lesson learned in this experiment so far has been that working with lots of small cakes instead of one large cake is quite the undertaking.  Oh.  My.
  • I can’t figure out if these things make me think of cartoon toasters, flying saucers, or football helmets.