Cake

• 5 cups flour
• 2 tablespoon baking powder
• 1 teaspoon salt
• 2 1/2 cups buttermilk
• 8 large egg whites
• 3 cups sugar
• 4 teaspoons grated lemon zest
• 2 sticks (16 tablespoons or 8 ounces) unsalted butter, at room temperature
• 1 teaspoon pure lemon extract
• strawberries

Buttercream

• 1 cup sugar
• 4 large egg whites
• 3 sticks (12 ounces) unsalted butter, at room temperature
• ¼ cup fresh lemon juice (from 2 large lemons)
• 1 teaspoon pure vanilla extract

For Finishing

• strawberries