This is an over the top lemon cake. It does for lemon what a Death by Chocolate Cake does for chocolate. It is a sumptuous lemon cake, filled with lemon curd, finished with lemon buttercream. The lemon flavor comes through in all elements of the cake while still balancing both sweet and tart. The curd remains tart, while the buttercream, like all buttercreams, is quite sweet.
Lemon Lover’s Lemon Cake
~ Makes One 3-layer Cake ~
- 6.6 oz. (1 1/2 cups less 1 tablespoon) arrowroot starch
- 6.2 oz. (approximately 1 1/2 cups) millet flour
- 2.4 oz. (6 tablespoons) potato flour
- 1.6 oz. (5 tablespoons + 2 teaspoons) garbanzo and fava flour
- 2.7 oz. (approximately 3/4 cup) flaxseed meal
- 17.6 oz. (2 1/2 cups) granulated sugar
- 2 tablespoons meringue powder
- 2 tablespoons baking powder
- 1/2 teaspoon baking soda
- 3/4 teaspoon salt
- 2-3 tablespoons grated lemon zest (from 2-3 lemons, use juice below)
- 1 teaspoon xanthan gum
- 6 large egg whites, room temperature
- 1 1/2 cup milk
- 2/3 cup canola oil
- 3/4 cup fresh squeezed lemon juice (3-4 lemons)
- 1 tablespoon vanilla extract
- 1/2 teaspoon lemon oil
- 6 large egg yolks
- 5.3 oz. (3/4 cup) granulated sugar
- zest of 2 lemons
- 1/3 cup fresh squeezed lemon juice
- 1/4 teaspoon lemon oil
- 4.0 oz. (1/2 cup, 1 stick) unsalted butter, cut into small cubes
Lemon Buttercream Icing*:
- 4.0 oz. (1/2 cup) unsalted butter, softened
- 3.5 oz. (1/2 cup) shortening
- 1/4 teaspoon salt
- 1 teaspoon vanilla extract
- 1/2 teaspoon lemon oil
- 2-4 tablespoons lemon juice
- 1 tablespoon meringue powder
- 1 pound (~ 4 cups) confectioners’ sugar
Heat oven to 350 F. Prepare three 9-inch cake pans by lining bottoms with parchment paper greased with butter. Do not grease the sides of the pans.
In the bowl of an electric mixer, combine the arrowroot starch, millet flour, potato flour, garbanzo and fava flour, flax seed, meringue powder, baking powder and soda, salt, lemon zest, and xanthan gum. Whisk dry ingredients until combined.
In a second bowl, whisk the egg whites until foamy. Add the milk, canola oil, lemon juice, vanilla extract, and lemon oil; whisk to combine.
On medium speed, beat liquid ingredients into dry ingredients until just combined, about 1 minute.
Remove bowl from mixer, using a silicone spatula stir batter to unsure it is thoroughly combined.
Divide batter among the pans, using an offset spatula to spread batter to the edges. Bake cakes for approximately 25 minutes until toothpick inserted in the center comes out clean and cake in lightly golden brown.
Allow cakes to cool in pans on cooling racks for 10 minutes; run a knife around edge of pan before turning out onto a wire rack. Reinvert cakes and cool completely.
In a heavy-bottom saucepan, combine the egg yolks and granulated sugar, whisk vigorously until light in color, 1 minute. Add lemon juice and zest, whisk for 1 minute.
Cook curd gently over low to medium-low heat, stirring continuously – 10 to 15 minutes, until curd had thickened and coats the back of a spoon.
Remove the pan from the heat, stir in the butter and lemon oil until smooth.
Cool curd to room-temperature, stirring occasionally. Cover curd tightly and chill for several hours before using.
In the bowl of a stand mixer, cream together the butter, shortening, salt, vanilla extract, lemon oil, and 2 tablespoons lemon juice. Add the meringue powder and confectioners’ sugar, mix on medium speed until thoroughly mixed; continue to blend for an additional minute or two until creamy.
Add additional lemon juice, blending well, to thin icing to desired consistency.
Place one cooled cake down on serving platter or cake board. Pipe a border (dam) of icing around edge of cake using an 8 or 12 tip and fill with 1/3 to 1/2 of lemon curd. (See here for complete instructions on adding filling between layers). Top with a second cake layer and repeat piping and filling steps before topping with final cake.
Optional, refrigerate cake until icing dam is hard; the solidified icing will keep the cake more stable, helping to prevent the cakes from sliding around and lemon filling from leaking out.
Decorate cake with remaining icing as desired.
*Depending on how much frosting you like and how you plan on decorating your cake, consider making one-and-a-half or double batch of icing to ensure you have enough.