Steps
1. Preheat your oven to 350°F (175°C) and grease a small round cake pan.
2. In a bowl, mix the flour, sugar, baking powder, baking soda, and salt until combined.
3. In another bowl, whisk together the milk, vegetable oil, and vanilla extract.
4. Pour the wet ingredients into the dry ingredients and mix until smooth.
5. Divide the batter into six small bowls. Add a drop of food coloring to each bowl, mixing well to create six different colored batters.
6. Layer the colored batters into the prepared pan, starting with red and working your way to purple.
7. Bake for 20-25 minutes or until a toothpick comes out clean. Let cool.
8. While cooling, prepare the frosting by creaming the softened butter and powdered sugar together, then adding milk to achieve desired consistency.
9. Once the cake is cooled, frost the top and enjoy with sprinkles if desired.