# how to increase a cake recipe



## perezio (Nov 9, 2007)

Hello pros,

I want to make a half sheet chocolate cake, but my recipe is for two 9 inch rounds. How would I go about increasing the recipe to accommodate the half sheet? how much batter do I know to put into the pan?

Thanks!


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## longfellow (Jun 11, 2008)

Height x Width x length= volume of square cake pan


PI ( 3.14)xRadius(half the distance from to opposite sides of a circlez) square
x height of cylander = volume of round cake pan


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## lessa (Jun 11, 2008)

but then how do you transfer from inches to volume? is it the old chemistry bar?


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## longfellow (Jun 11, 2008)

the volume for a nine inch x two inch round pan is 127 inches

I don't know the volume of the square pan but let say the the pan is 24inch long and 18 inches wide and two inches deep your total volume would be 864

now divide that number (853) by 127 which will give you 6.8 round up to 7. So you would have to increase ingredients 7 times. if it calls for two eggs you now need 14 eggs, if recipe called for 3 cups of flour now you need 21 and on and on.


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## perezio (Nov 9, 2007)

Ah, very good. That makes sense. Thanks!


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## lentil (Sep 8, 2003)

I think you may be off. A half sheet is only about 1 inch deep and is 11x17. My 2 layer cake doubled fits a hotel pan which is roughly the same size only deeper. Normally we do the recipe once and it comes up about an inch in the hotel. We then top it with cheesecake and bake or after the cake is baked, german topping (coconut, nuts, cream, and butter) for a german chocolate cake square. 

I thing 7x is going to give you way too much batter., but I've been wrong before.


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## boar_d_laze (Feb 13, 2008)

911's math is good, but his sizes are wrong. Lentil is mostly right. However, no cigar yet. 

Most half sheets are very close to 18 x 13, and not 17 x 11. The correct conversion from 1" tall 9" round to a half sheet is a factor of 3 -- assuming the half sheet is, indeed a half sheet. If, on the other hand, it's a jelly roll (10 x 15), which are very common in home kitchens and sometimes confused as half sheets, the correct factor is 2. If, on the third hand, the 9" recipe bakes higher than 1", you'll have to adjust for the lower sides of your rectangular pan. I suggest making the full amount according to the conversion factor and reserving extra batter for deep frying peach slices. 

Good luck,
BDL


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## longfellow (Jun 11, 2008)

I was only given him general info so he could do the math the pan sizes are just abstact so that he could plug in the numbers and be able to do conversions on any size pan.


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## boar_d_laze (Feb 13, 2008)

I like an optimist, and find your faith in peoples' desire to do geometry refreshing. 

BDL


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