Lemon Cake with White Chocolate Lemon Buttercream and Lemon Curd Filling
This cake is based on a lemon cake from the book Rose's Heavenly Cakes
6oz White Chocolate
6 large egg yolks
1 cup milk
1 1/2 tsp vanilla
3 cups cake flour
1 cup sugar
3/4 tsp salt
4 tsp baking powder
1 Tbsp lemon zest
9 Tbsp unsalted butter
Start by making the Lemon Curd and then the White Chocolate Lemon Buttercream (below). They need to be made 4 hours ahead of time.
Preheat oven to 350ºF
For cake, melt white chocolate and set aside to cool. Mix egg yolks, milk and vanilla in a small bowl. Combine flour, sugar, baking powder, salt and lemon zest in a large mixing bowl. Add butter and mix until well combined. Add egg mixture a little at a time until combined. Add melted chocolate and mix until smooth. Don't over-mix. Spread into two 8" cake rounds (greased and floured). Bake at 530ºF for 25 minutes or until done. Cool completely. Fill layers with lemon curd and frost with buttercream.
Lemon Curd Filling
3 Tbsp lemon zest
7 large egg yolks
1 cup sugar
6 Tbsp unsalted butter
1/2 cup lemon juice (from about 3 lemons)
1/4 tsp salt
In a medium sauce pan, whisk the yolks, sugar and butter until well blended. Whisk in lemon juice and salt. Cook over medium-low heat until curd is thickened. Do not allow to boil or it will curdle! This might take some patience. I suggest listening to an audiobook or watching a show while doing this. I was over the stove for 20+ minutes. Allow curd to cool in refrigerator in an airtight container for 3-4 hours.
White Chocolate Lemon Buttercream10.5 oz white chocolate
20 Tbsp unsalted butter (divided)
4 large eggs
Melt white chocolate without much heat (over double boiler if possible). Whisk in eggs and heat to 140ºF while stirring. Cover and refrigerate. Stir the mixture every 15 minutes until cool to the touch. whip in butter (using whisk attachment on mixer) until peaks form. Refrigerate, covered, for 3 - 4 hours.
Right before frosting cake, whip again and add about 1/2 cup of the lemon curd to the buttercream icing.