I'm making my first full sheet cake this week and could use some help. It will be chocolate. I'm wondering how much batter I will need (my recipe makes 9 in round) and how much buttercream to fill and ice. Also, I'd appreciate any tips on oven temp and length of cooking. I do have a heating core. My pan is 24 x 18 I believe. It is big enough that I have to use a commercial oven. Thank you!!
Use the Wilton chart and double the batter & icing amounts listed for half sheet--12 x 18.
If the commercial oven isn't yours, ask the owner for tips using their oven... I would think they bake full sheets quite often. Do you have cardboard bakeable trays that are used inside the full sheet pans? Also, if the oven isn't yours, wouldn't it be easier to just bake two half sheets to place side by side?