• Step 1: Preheat your oven to 350°F (175°C). Grease and flour three 9-inch round cake pans.
• Step 2: In a medium bowl, whisk together the flour, baking powder, and salt. Set aside.
• Step 3: In a large bowl, cream the softened butter and sugar until light and fluffy, about 3-4 minutes. Beat in the eggs one at a time, then stir in the vanilla extract.
• Step 4: Alternate adding the flour mixture and milk to the butter mixture, mixing just until incorporated. Divide the batter evenly between the three prepared cake pans.
• Step 5: Bake the cakes for 18-22 minutes, or until a toothpick inserted in the center comes out clean. Allow the cakes to cool in the pans for 10 minutes, then transfer them to a wire rack to cool completely.
• Step 6: In a medium bowl, beat the softened butter for the frosting until creamy. Gradually add the powdered sugar, lime juice, and lime zest, mixing until well combined and smooth.
• Step 7: Divide the frosting into three equal portions. Tint one portion green with the green food coloring, and tint another portion red with the red food coloring. Leave the third portion white.
• Step 8: Place one cake layer on a serving platter or cake stand. Spread the strawberry preserves over the top. Top with the second cake layer and spread the green frosting evenly over the top and sides. Top with the final cake layer and spread the red frosting over the top and sides. Use the white frosting to create clean, straight edges between the colored layers.