The cake part is French Vanilla from a plain old Betty Crocker mix. The buttercream is homemade using the recipe I learned in my Wilton class.
1 cup vegetable shortening
1 tsp clear vanilla extract (make sure it's the clear kind so you end up with true white icing)
1/8 tsp butter flavour
2 tbsp water
1 lb (approx 4 cups) icing sugar
1 tbsp meringue powder
Pinch of salt
Cream shortening, flavoring and water. Add all other ingredients and mix on medium speed until thoroughly mixed together. Blend until creamy.