Question: 1/2 sheet cake how many cake mixes?
Answer: 4 mixes would make a nice tall cake! I use 2 in each, then trim the dome off and stack them, it makes the cake a bit higher, which looks nice. It's only around a dollar for each (if I get them at WalMart, not my supermarket) and that's easier for me than mixing three and dividing it in half.