I'm going to spatchcock a 13 lb turkey but I'm concerned that I my roasting pan won't be big enough to contain the bird once it's butterflied flat. My roasting pan is 17" x 13" with high sides. Is that big enough? Do I need a bigger pan?
I think it will probably be ok. May have to push it in a bit in the beginning but as it roasts should fit.
I use a sheet pan with a silpat (or parchment paper).
If concerned about size, wrap a piece of string around the birds chest, deduct an inch for the spine to be removed, then you will know the width needed in the pan before you commit to cutting it up.