1 cup butter, softened
1 ½ cups white sugar
2 whole eggs
3 egg whites
1 teaspoon vanilla extract
½ cup sour cream
2 ½ cups all-purpose flour
1 teaspoon baking powder
½ teaspoon baking soda
½ teaspoon salt
Red, green, blue and yellow food colouring
- Mix the butter and sugar in a bowl until fluffy and creamy.
- Stir in the eggs, egg whites, vanilla and sour cream and mix well for a few minutes.
- Sift the flour with baking powder, baking soda and salt then fold it in the batter.
- Split the batter into 4 smaller bowls then add a drop of food colouring into each bowl and mix slowly with a spoon in each batch of batter.
- Spoon the colourful batter into a 9-inch cake pan lined with baking paper.
- Using a toothpick, swirl the batter around to mix the colours.
- Bake in the preheated oven at 350F for 35-40 minutes.
- Allow the cake to cool in the pan then slice and serve.