Preparation Steps

• Preheat oven to 350°F and grease a 9x13-inch baking dish.
• In a large mixing bowl, beat the cake mix, water, egg whites, oil, sour cream, and vanilla until combined. Mix on low for 30 seconds, then on medium for 2 minutes. Scrape down sides of the bowl.
• Pour 2 cups of batter into the prepared pan.
• Divide the remaining batter into three bowls. Add a few drops of blue, pink, and yellow food coloring to each bowl, stirring until desired color is reached.
• Drop spoonfuls of each colored batter randomly on top of the white batter. Use a knife to swirl the colors together.
• Bake for 30-35 minutes or until a toothpick inserted comes out clean. Cool completely before frosting.
• For the frosting, whip the butter until fluffy, then add powdered sugar and salt. Beat until combined. Mix in vanilla and 2 tablespoons of heavy cream. Adjust consistency with more cream if needed. Color frosting as desired.
• Frost the cooled cake and decorate with Easter sprinkles.