I am using a WASC cake mix extender recipe for a chocolate cake. I never, ever have issues with white cake when I use this, but for the chocolate, centers really sink. I am at a loss. The only thing I tweak is that instead of 1 c flour, I use 2/3 c flour and 1/3 c cocoa plus I add 1tsp baking powder. Still use all the same amount of liquid as with the WASC cakes. I use a flower nail in the center of the pan, too. Any suggestions? Thanks!!

I never change the recipe except for leaving the almond out and putting in adding a 2 heaping tablespoons of cocoa to the recipe and I never have a problem, Maybe you should not put the baking soda and use the entire cup of flour and see how it turns out.

Pat, I am going to try that. No baking powder and full cup of flour, plus the cocoa. Will post how it turns out! Thanks!

I did several things to fix my problems. First, I switched to Betty Crocker cake mix. Not sure if it mattered but it looks better. Second, I followed what Pat said and followed the WASC cake extender recipe to a T, only adding 2tbsp of cocoa and 2 tbsp of instant coffee to my 1/2 c water. Did not change amt of liquid, just flavored it. Finally, and most importantly, I bought an oven thermometer. Guess what... Oven was running 15 degrees under. So I have had to adjust my temp to 365 so that it holds steady inside the oven with the cake pan at 350 . Accurate baking temp is probably key!! I advise anyone having an issue with their cakes to get an oven thermometer!! It was only $6 at a restaurant supply store and completely worth my peace of mind!

I bake all of my cakes at 325* and haven't had a problem with the sinking.

I'm thinking maybe it was the baking powder more than anything.

Is the center done when it sinks? Sometimes that's a sign it's underbaked. Regardless of the size of the layer, I will put in a flour nail, especially if I'm making a 6x3 layer.

When I want to use a doctored mix recipe, I use this recipe for my WASC and use a chocolate cake mix.

http://cakecentral.com/recipe/the-original-wasc-cake-recipe

Are you doctoring a white cake to make it chocolate? Or adding cocoa to make it more chocolaty? The beauty of the WASC recipe is that it can be used with any flavour cake mix.

I've also used this recipe with great success.

http://cakecentral.com/recipe/amazing-chocolate-wasc-cake

And my all time favourite for a major hit of chocolate is this one. Scroll into the comments for the actual recipe.

http://cakecentral.com/recipe/triple-chocolate-fudge-cake

And I also have started baking at 325F.

I've had this problem in the past too-even posted about it. No other flavor do I have a problem-just chocolate. I only add coffee to the recipe and I use the WASC for chocolate cake recipe. Thinking about searching for best scratch and nixing this one. I've got 2 scratch recipes that are really good...