I ended up multiplying this recipe x1.5 (changed the servings from 12 to 18) so I wouldn't have a "flat" cake like the other reviews complained about. I had to bake it about 40 minutes at the same temp. It was perfect. I got a very plump 13x9 cake. Tasted great. I also used regular all purpose flour and it turned out fine. Perfect for my work potluck.