Preheat the oven to 350°F (175°C). Grease and flour two 9-inch round cake pans.

In a mixing bowl, combine flour, sugar, baking powder, and salt.

Add softened butter, milk, eggs, and vanilla extract. Beat on medium speed for 2 minutes until smooth.

Pour the batter evenly into the prepared cake pans.

Bake for 25 minutes or until a toothpick inserted in the center comes out clean.

Let the cakes cool in the pans for 10 minutes, then remove from pans and cool completely on a wire rack.

In a mixing bowl, beat the softened butter until creamy.

Gradually add powdered sugar, alternating with heavy cream, and beat until fluffy.

Mix in vanilla extract and beat until well combined.

If desired, add food coloring and mix until the desired color is achieved.

Place one cake layer on a serving plate and spread a layer of buttercream frosting on top.

Place the second cake layer on top and frost the top and sides of the cake with remaining buttercream.

Decorate as desired and serve.