Mary Berg's Rainbow Cake

Makes 1 Bundt (or 2 rainbow cakes)

Ingredients:

½ cup unsalted butter, room temperature

1 cup sugar

2 large eggs

1 ½ teaspoon vanilla

1 cup full fat plain or vanilla yogurt

2 cups all-purpose flour

1 teaspoon baking powder

1 teaspoon baking soda

¼ teaspoon salt

Red, yellow, and blue food colouring

1–2 tubs store bought vanilla buttercream

Directions:

1. Heat your oven to 350ºF and lightly grease a standard Bundt pan with non-stick cooking spray. If you do not have a Bundt pan, a 10-inch round cake pan or 9-inch square cake pan will work. You won’t get the same rainbow look with the end result, but it will still be fun to decorate
2. Using a hand or stand mixer fitted with a paddle attachment, cream the butter and sugar together until pale and fluffy, about 1 to 2 minutes. Add in the eggs one at a time, beating well after each addition, then stir in the vanilla extract and yogurt.
3. In a separate bowl, whisk together the flour, baking powder, baking soda, and salt. Add the dry ingredients to the wet and stir just to combine. Divide the batter into three separate bowls and colour each with a few drops of the food colouring.
   
4. Starting with the red or pink batter, pour it into the prepared pan followed by the yellow and the blue. If desired, run a long skewer or thin knife through the batter to swirl the colours slightly but this is not necessary – you’ll still get nice layers if you leave the batter as is.
   
5. Bake the cake for 40 to 45 minutes or until a toothpick inserted into the cake comes out clean. Set aside to cool completely in the pan.
6. Meanwhile, divide the buttercream into three bowls and colour with the food colouring.
   
7. When the cake is cool, turn it out and cut it in half to form 2 semicircles. Stand each on their end and decorate like a rainbow with the multicoloured buttercream. You can do this with a butterknife, an offset spatula, a piping bag or zip top bag with the corner cut off, or even the back of a spoon.