Some people love Chocolate, and others like Lemon. If you have a Lemon Lover in you life, this is the cake for them. This recipe is a combination & adaptation of several different recipes. A fluffy, moist cake combined with mascarpone filling topped with Lemon Curd to build up the 6″ layers. Put them all together covered in decadent Lemon Swiss Meringue Buttercream Frosting, and you get Paul’s Lemon birthday cake.

One of my Quarantine shopping expeditions delivered this adorable cake pan set from Wilton linked up here. Wilton 5 small 6″ cake pan set

5 small 6″ cake pans that make the perfect small layer cake.

Of course, Wilton always sends recipes & ideas with the new pans. So, I started brainstorming on what could be delicious. It took a few attempts to get the flavor that I wanted and the texture of the cake. After a few overflows on the little pans, the following recipe was born. Each pan bakes 1 cup of this batter without overflow. I set the pans inside of a jelly roll pan with about 1 1/2 cups of water to keep the cake flat.

This recipe used almost every single bowl, mixer, sifter, spoon, and spatula in my kitchen. The result was a moist, delicious lemon concoction that left the whole table smiling.

Let’s start with the recipe. I recommend weighing out the flour to get the right consistency in the crumb, especially when using cake flour. You can use all-purpose flour if that is all you have; leave off the 2 extra TBSP of flour. The weight of either flour should actually be very close to 240 g.

Ingredients & Instructions

Cake

• 2 cups + 2 TBSP Cake Flour (240 g) – I use Swans Down
• 1 1/2 tsp baking powder – Clabber Girl is my favorite.
• 1/2 tsp baking soda – Clabber Girl
• 1 tsp salt
• 10 TBSP Unsalted Butter at room temperature – store brand is good.
• 1 1/4 cup granulated sugar
• 3 eggs at room temperature
• 1 tsp vanilla extract
• 2/3 cup whole milk
• 3 TBSP lemon zest, about 3 lemons
• 1/3 cup fresh lemon juice, use the same 3 lemons

Instructions for Cake

1. Preheat the oven to 350 degrees.
2. Butter and flour the 6″ cake pans
3. Whisk together the flour, baking powder, baking soda, and salt. Set bowl aside.
4. Combine the whole milk and lemon juice, and set aside.
5. Combine the sugar and lemon zest in a food processor to completely mix.
6. In a stand mixer fit with a paddle attachment, cream the butter and sugar/zest mixture.
7. Add eggs and vanilla one at a time, and mix until incorporated.
8. Scrape down the sides with a Mix N Scraper.
9. Alternate adding 3 flour additions and 2 milk/lemon juice additions and mix throughly, again scraping down the sides with each addition.
10. Spoon 1 cup + 1 TBSP of batter into each pan for baking.
11. Bake at 350 for 23-25 min, alternating position in the oven half way through for even baking, until a cake tester comes out clean.

Filling

• 8 oz mascarpone room temp
• 1/2 cup heavy whipping cream
• 1/4 cup powdered sugar
• 1 tsp lemon extract
• 3 TBSP lemon zest

Instructions for Filling

1. Beat the whipping cream with the lemon extract until it has stiff peaks.
2. Gently fold the powdered sugar and zest into the mascarpone.
3. Mix the whipping cream mixture into the sweet mascarpone.
4. Refrigerate for about 30 min while you make the Lemon Curd.

Lemon Curd

• 3 egg yolks
• 1/2 cup granulated sugar
• 2 TBSP cornstarch – Clabber Girl
• 1 TBSP Lemon Zest, about 1 lemon
• 3 TBSP Fresh Lemon Juice
• 1/4 cup unsalted butter, cold

Instructions for Lemon Curd

1. Separate eggs; reserve the whites for frosting.
2. Whisk the yolks lightly to make smooth.
3. Add the sugar and whisk until thickened and smooth.
4. Completely dissolve the cornstarch in the lemon juice.
5. Combine all ingredients except butter in a small sauce pan. Heat on medium low stirring with a whisk constantly until the mixture reaches 168 degrees. (It will coat the back of a wooden spoon.) Don’t boil this mixture.
6. Turn off the heat and whisk in the cold butter until completely melted and combined. Set it on the counter covered with plastic wrap, and let it cool completely.
7. I usually put the mixture in a ziplock bag or piping bag for use later.

Lemony Swiss Meringue Buttercream Frosting

• 4 egg whites, large
• 1 1/2 cups sugar
• 1 lb butter room temperature (69-75 degrees)
• 3 TBSP lemon zest

Instructions for Frosting

1. Whisk together egg whites and sugar in a double boiler. If you don’t have a double boiler, you can use a glass bowl over a pot of simmering water, but don’t let the bowl touch the water.
2. Whisk continuously until the mixture reaches 165 degrees on a candy thermometer. Transfer this mixture to a stand mixer with a whisk attachment. Mix on high for 3-4 minutes; then, mix on low until it cools to room temperature.
3. Change to the paddle attachment, and add butter one tablespoon at a time followed by the lemon zest.

Note: If the buttercream is too soupy, pop it in the refrigerator for about 10 min and rewhip. If the buttercream is too greasy, it is too cold. Place the bowl over a steaming water bath. It will loosen up as it reaches 72 degrees. If you measured something wrong, start over, but most of the time, SMBC can be fixed with temperature.

Time to Assemble the Cake

Make sure the layers are completely cooled to room temperature.

1. Place the first layer on the plate or cake board. Spread a thin layer of cooled mascarpone filling, and drizzle the lemon curd on top. The curd will actually help keep the cake moist and delicious while it adds flavor.
2. Repeat with the remaining layers leaving the top layer without filling and smooth top side facing up.

3. Finally, it is time to frost. Give the Buttercream a final whip in the stand mixer. You can easily color this frosting for decoration. I chose to leave mine white because the birthday boy likes minimal icing and more flavor in the cake.

This post has several affiliate links to my favorite places and products. If you make this cake please tag me @jennskitchenblog on Instagram and use #jennskitchenblog

Happy Baking, Friends!