I am baking a cake for my daughters preschool - 13 students, plus a potential of 4 + guests per student - so possibly 52 people. I am wanting to do a slab style cake - my pan is 12 X 18. Should I make 2?

Your pan serves 54. I wouldn't bake two unless you think the + could possibly mean potentially another 52 or so people.

you could always do two layers and tort/fill them.. This way, everyone gets a slightly bigger piece of that..Just an idea though.

Thanks for your input! I will make one and torte it. BTW, I guess slab cakes are not usually stacked like I have done with round cakes?