Pre-heat oven to 400 degrees.
Beat sugar and eggs over medium speed until creamy.
Mix flour and baking powder together and add to sugar mixture alternately with milk. Mix until all ingredients are incorporated.
Add melted butter and vanilla and beat until smooth.
Gently fold in rainbow sprinkles.
Line 2 large baking sheets with parchment paper; drop batter by heaping tablespoons about 2 inches apart on parchment paper.
Bake 7-9 minutes or until light golden brown and center springs back when touched.
Drizzle with glaze and serve warm or at room temperature. (*Note: muffin tops can also be eaten plain, without glaze, and are delicious......just not quite as fun!)