Red Velvet Cake with Cream Cheese Frosting

For the red velvet cake:
1. Preheat oven to 350 F.
2. Grease and flour three 9-inch spring form cake pans, then line the bottoms with parchment paper.
3. In a small bowl, mix together the food colouring, cocoa powder, and vanilla. Set aside.
4. In a large bowl using an electric mixer, cream together the butter or margarine and sugar until fluffy, about 4-5 minutes. Add the eggs, one at a time, beating well between each addition.
5. Add the flour in three portions, alternating with the buttermilk, beating well after each addition.
6. Beat in the salt and the cocoa mixture, until fully incorporated.
7. In a small bowl, mix together the vinegar and baking soda. Stir this into the batter until completely incorporated.
8. Divide the batter between the three pans and smooth the top.
9. Bake for 20-25 minutes, or until a toothpick inserted into the centre of the cake comes out clean. Remove from oven.
10. Let cakes cool in their pans for 10 minutes; remove from pans and let them cool completely on a wire rack.
11. When cakes are cool, stack, fill and frost with cream cheese frosting.

For the cream cheese frosting:
1. In a large mixing bowl using an electric mixer, beat the cream cheese and butter until smooth.
2. Add the vanilla extract and the sugar, beating slowly until incorporated.
3. This makes enough frosting for one three-layer nine-inch cake.