Preheat the oven to 350°F (175°C). Grease and flour two 9-inch round cake pans.

In a mixing bowl, cream together the softened butter and granulated sugar until light and fluffy.

Add the eggs one at a time, mixing well after each addition. Stir in the vanilla extract.

In another bowl, combine the flour, baking powder, and salt. Gradually add to the creamed mixture, alternating with the milk.

Add blue food coloring until the desired color is achieved.

Divide the batter evenly between the prepared cake pans.

Bake for 25-30 minutes or until a toothpick inserted into the center comes out clean. Let cool in pans for 10 minutes before transferring to wire racks.

In a mixing bowl, beat the softened butter until creamy.

Gradually add the powdered sugar, mixing well. Add vanilla extract and milk to achieve a smooth consistency.

Add blue food coloring until the desired color is achieved.

Place one cake layer on a serving plate. Spread a layer of frosting on top.

Place the second layer on top and frost the top and sides of the cake.

Decorate with edible pearls and whipped cream if desired.