Preheat your oven to 350°F (175°C).
Grease and flour two 9-inch round cake pans.
In a bowl, whisk together flour, baking powder, and salt.
In another bowl, cream butter and sugar until light and fluffy.
Add eggs one at a time, mixing well after each addition.
Stir in vanilla extract.
Gradually add dry ingredients to the wet mixture, alternating with milk.
Fold in rainbow sprinkles gently.
Pour batter evenly into prepared pans.
Bake for 30-35 minutes or until a toothpick comes out clean.
Allow cakes to cool in pans for 10 minutes, then transfer to wire racks to cool completely.