I make 1/2 sheet cakes for alot of different occasions and have used the chocolate butter cake recipe in the cake bible in the back for the 2 / 12 x 2 in pans (round). I was rereading some things and I was wondering if I should be adjusting the baking powder because of the size. I do wish Rose would tackle this question in her book because ALOT of us do those type of cakes and I would like to convert some of her recipes but frankly, I don’t always have the time (work a full time job besides my cake business) or want to waste ingredients (money) on something that may not turn out. I don’t want to have to always do practice cakes either. Round cakes are beautiful, but sheet cakes are practical for alot of different celebrations.