Grease two 9”x 2” round pans (Wilton Cake Release works well).
In medium bowl, stir together flour, baking powder, & salt. Set aside.
Preheat oven to 350°.
In mixing bowl, cream butter & sugar till well combined.
Add 1 drop Super Red coloring. Beat to combine.
Add eggs 1 at a time, beating well.
In separate bowl, stir together milk, lemonade, & lemon extract.
Alternately add flour mixture & milk mixture to butter mixture. Beat on low till just combined.
Remove half of batter & spread in one pan.
In remaining batter, stir in 2 drops Super Red color. Spread in 2nd pan.
Bake about 30-40 min until tops spring back when touched.
Cool 10 min on wire rack. Remove from pans; cool completely.
Trim off domed tops of layers so cakes are flat. Cut each layer horizontally in half to create 4 layers.
Place 1 dark-pink layer, cut side down, on serving plate.
Frost with lemonade buttercream icing, and top with light-pink cake layer. Repeat using remaining layers.
Frost entire cake.