Preheat oven to 350 degrees F (175 degrees C). Line 6 muffin cups with paper liners.
Beat butter and sugar together in a bowl using an electric mixer until creamy; beat in egg and vanilla extract. Stir flour and baking powder into creamed butter mixture until combined; stir and almond milk until batter is smooth. Spoon batter into the prepared muffin cups.
Bake in the preheated oven until cupcakes are lightly browned, 20 to 25 minutes. Cool cupcakes completely, about 30 minutes.
Mix 1/2 cup frosting and food coloring together in a bowl until color is even. Spoon the remaining 1/4 cup frosting into a small plastic bag and cut a small hole in the bottom corner.
Frost the cooled cupcakes with blue frosting and then draw a star on top using the white frosting piping bag.