White Cake with Chocolate Filling

To make the cake, beat the eggs with 1/2 cup of granulated sugar and add the unsalted butter and flour

Fold in the egg whites and lemon juice

Bake in a greased pan at moderate heat until a toothpick inserted into the center comes out clean

Let cool completely

To make the filling, combine the granulated sugar and water in a saucepan over medium heat

Bring to a boil, then reduce heat and simmer until the sugar dissolves

Slowly pour the melted chocolate into the egg mixture, whisking constantly until smooth

Add the softened butter and mix until combined

Do not overmix

To assemble the cake, place one layer on a serving plate, spread with the filling, and top with another layer

Repeat this process two more times

Couverture: Combine the flour and cream of tartar in a saucepan

Gradually add boiling water, whisking constantly until smooth

Remove from heat and let cool to room temperature

Pour the couverture over the cake, spreading evenly to cover the entire surface

Let set before serving.