but it's been ages (like 5 years) since I've done a sheet cake.

They want it for 15 people so I suggested a 1/4 sheet.

So here are my dork questions for the day:

1) How many cake mixes do I need to use? (I think I used to use 2 & can't find my notes...lol)

2) and how long would you bake it for?

I'm in a bit of a panic over my second question because I went to do a cake today and it took almost an hour to cook but it came out great! (ok so I used to much batter in the pans and I confess!!! Please pelt me with the crumbs, I beg of thee!)

She is a good friend and asked for transformers characters on the cake and I nicely explained "sorry I can't due to copyrights". She was cool with that and then said "I'd like it with a robot theme"

He's turning 7 and will never know the difference! He'll call it what he wants and be happy because it's cake with frosting and it's got a robot so that must mean it's a transformer!

I don't do cake mixes a lot, but I would say that two cake mixes are correct.

According to the Wilton baking chart, the baking time for a 1/4 sheet or 9"x"13"x2" at 350 Farenheit is 35-40 minutes.

Good luck!

One cake mix in a 9X13 pan will give you about a 2 inch high cake. If you use an extender it will be slightly taller.
For one cake mix, I bake about 25 minutes at 325 F, then start checking it every 5 minutes or so if it's not done.

I'm sure it is probably very late & you have already baked but here is the information you need.
How many mixes will depend on the size of the '1/4 sheet' you are using.
For my '1/4 sheet' I use a 12x8x2 and it uses one mix perfectly. For a 9x12(or 13)x2 you need 1 1/2 mixes.
Baking time for (most) one mix pans would be about 20-30 minutes. If it is taking more than 35 minutes to bake up right you oven may need adjusting. I bet you need to get it calabrated

I usually use the WASC recipe in half (one box, plus sugar, flour, etc) and it gives just under 8 cups of batter. I use that for each layer of the 9X13" cake. 1 layer to feed 20, 2 layers to feed 40.

HTH

Jen

ok I just checked my pan... It's a 9X13X2.

I do have an oven thermometer in there and it thankfully is right on target and baking at the right temps.

I think I better play it smart and do a test cake tomorrow. hehe