Cost per Serving:
1. Preheat oven to 350°F. Line a muffin tin with liners; set aside.
2. Using an electric mixer, cream butter and sugar at medium-high speed until fluffy, about 3 minutes. Add eggs one at a time, beating after each. Mix in vanilla, baking powder and salt at low speed. Gently blend in half of flour. Mix in milk then remaining flour at low speed until smooth.
3. Spoon batter in equal amounts into prepared cups. Bake until a tester inserted in middle of cake comes out clean, about 20 minutes. Let cool completely before decorating.