I put three boxes of treats plus 3 1/2 bags of marshmallows plus 2 1/4 sticks of butter into a 12x18x2 pan. One batch was made at a time and just layered one on top of the other and it worked fine.
I drizzled some Callebeaut Brand white and milk chocolate that I melted over a double boiler.
Then sprinkled with pretty pink "jimmies".
Butter the pan very well and after the treats refrigerate for a while, tip them over and they will pop right out of the pan. I took out a large knife and cut them in long strips and then cut smaller squares out of each strip.
Then each was wrapped up with an ingredient label on teach one...(kind of a pain, I will admit, but with all of the allergies these days, the food inspector requires it)...and brought over to the Church Faire for sale at the bake table.