I use the cake mix extender where I add an egg, 1 c of flour, 1 c of sugar an 8oz sour cream, a splash of vanilla and a pinch of salt to the cake mix. Works GREAT with all DH or BC mixes that I've used. BUT the only thing I have in my cabinets right now is butter recipe and I dont want to go to the store since I live 10 minutes from town and this is a FREE cake. I was wondering if anyone out there new how I would extend this type of cake mix. How much more butter would I add? If any.

I only use the DH's Butter recipe with the extender. It tastes great. I use 1/4 cup butter and 1/4 cup canola oil. I also cut down on the sugar to 1/2 cup. Use cake flour and Watkins vanila. Yum!