Ingredients:
For the Cake:
- 2½ cups all-purpose flour
- 2 tsp baking powder
- ½ tsp baking soda
- ½ tsp salt
- 1 cup unsalted butter, softened
- 1½ cups granulated sugar
- 4 large eggs
- 2 tsp vanilla extract
- 1 tbsp fresh lemon zest
- ½ cup fresh lemon juice
- 1 cup buttermilk
For the Lemon Buttercream:
- 1 cup unsalted butter, softened
- 4 cups powdered sugar
- 2–3 tbsp fresh lemon juice
- 1 tbsp lemon zest
- 2–3 tbsp milk or heavy cream
- 1 tsp vanilla extract
- Pinch of salt
For the Lemon Filling:
- ½ cup lemon curd
Method:
- Preheat oven to 350°F (175°C). Grease and line two 9-inch round cake pans.
- Whisk together flour, baking powder, baking soda, and salt.
- Beat butter and sugar until light and fluffy.
- Add eggs one at a time, beating well after each addition. Mix in vanilla and lemon zest.
- Combine lemon juice and buttermilk. Add the dry ingredients to the butter mixture alternately with the buttermilk mixture, beginning and ending with the dry ingredients.
- Divide the batter evenly between the pans and bake for 25–30 minutes, until a toothpick comes out clean.
- Cool in the pans for 10 minutes, then transfer to a wire rack to cool completely.
- Make the frosting: Beat butter until creamy. Gradually add powdered sugar, then lemon juice, zest, vanilla, salt, and enough milk or cream to reach a smooth, spreadable consistency.
- Place one cake layer on a serving plate. Spread lemon curd over the top, leaving a small border around the edge.
- Add the second cake layer and frost the top and sides with lemon buttercream.
- Garnish with thin lemon slices or extra lemon zest if desired.
- Chill for 30 minutes, then slice and serve.