I’m using Betty Crocker butter cake mix and trying to bake 10” and 12” layers both in 3”deep pans. They keep falling in the center!  I’ve never had this problem and have no clue what is wrong. Any help?  Should I not grease and flour the sides? I use a flour nail or cake core and have even tried using baking strips... nothing has worked. I’m down to the wire please help!

Using 3” deep pans has a whole different way than 2” ones  K8  is the expert one for them   Did you fill the pan 1/2 full?  Can’t remember what else is different 

I just baked a 12" cake use DH mix in the WASC recipe.  I used two flower nails and did not grease or flour the sides, just put in a piece of parchment on the bottom.  DId you by any chance open the oven door while the cakes were baking?  I find that if I do this and the cakes aren't fully done they tend to fall a bit, especially the chocolate version.