I'm interested in trying a devil's food chocolate cake recipe, but want to make it in a 9x13x2 inch pyrex rectangular pan (roughly 10-12 cup) instead of an 8x2 or 9x2 inch round (roughly 7 or 8 cup). Honestly, I'm lost on whether this is doable. Any advice at all appreciated (e.g. lower temp/longer time, same temp/longer time, don't try it, structure of cake inadequate to support it over bigger area).
Also, I want to bake some cupcakes using a standard butter cake recipe. My understanding is that I can almost certainly do this, should just keep temp same but reduce baking time by 1/3 to 1/2. Does this sound accurate?