Originally Posted by dona and ray
how do I make an ice cream cake (9 X 13 pan) and what is the best frosting for decorating same
Welcome to DC.
Can you show us the recipe? Are you sure you want to use frosting on an ice cream cake? You could drizzle the top with chocolate syrup... but without seeing the recipe, don't want to guess.
A few ideas:
You could make brownies in two pans (for the cake), let them cool & layer with semi-melted ice cream, another layer of brownies, and freeze.
Another option is, pressing cookie dough into the pan (as a base), baking, cooling, topping with ice cream, then sprinkle toppings of choice (nuts etc) and freezing -- an ice cream pie. I have a recipe for peanut butter ice cream pie. If you're interested, pm me.
Yet another option is, an ice cream sandwich cake, made with ready-made ice cream sandwiches.
The size of the dish used may or may not depend on the recipe; but we can help you adapt, if you have a certain recipe in mind.