7hr 55min · 20 servings Ingredients For the Lemon Cake 3 cups (390g) all-purpose flour 1/4 tsp baking soda 2 3/4 tsp baking powder 1 tsp salt 1 1/2 cups (336g) unsalted butter, room temperature 2 cups (414g) sugar 4 egg whites 1 1/2 tsp vanilla extract 1 1/4 cups (300ml) milk 1/4 cup lemon juice 2 tbsp lemon zest For the Lemon Buttercream 2 1/4 cups (504g) unsalted butter, room temperature 9 1/2 cups (1093g) powdered sugar 1/2 tsp salt 1 tsp vanilla extract 2 tsp lemon zest 2–3 tbsp lemon juice Yellow gel icing color For the Lemon Curd 1/4 cup (60ml) fresh lemon juice (about 1–2 lemons) 2 tsp finely grated lemon zest 1/3 cup (69g) sugar 4 egg yolks 2 tbsp (28g) salted butter For the Lemon Bavarian Cream 1 1/2 tsp powdered gelatin 4 1/2 tbsp (68ml) lemon jui