i have celiac disease so decided to try a betty crocker gluten free, yellow cake mix. it is a 15 oz. mix. i also don't like to add melted butter, so thought i'd try hard butter and use my food processor to make a crumb topping. because this was a 15 oz. box -vs 9 oz., i decided to use 12 T. of butter, rather then 8. using my chopping blade, i mixed the cake mix with 12 T. of butter, and 1 T. cinnamon, and then put it in the refrigerator. i peeled/cored/sliced 9 gala apples (4.41#)..do not use the thinest slicer. i poured some vanilla into the sliced apples (did not measure 'cause i LIKE vanilla). i put the apples in the bottom of a 9x13 cast iron baking pan, and the refrigerated crumb topping (added walnuts maybe 1/2 c. chopped walnuts to the crumb mixure....my husband LOVES walnuts) over the apples. i baked this at 350 degrees for an hour....i was anxious to see how it turned out.....SCRUMPTIOUS. especially warm with some french vanilla ice cream. I hope this helps anyone who has celiac disease.