While supplies needed for different styles of freezer cooking sessions, varies somewhat, there are some that are more convenient to have on hand than others. This does not mean that you are supposed to run out to the store, and purchase all these items if you do not have them already.
You can do just that, but I would recommend seeing first, how often you actually use each individual item and if they really warrant a purchase. In the meantime, try to borrow from friends, family and neighbors. If you ask them, usually they are quite willing to lend it to you, one or two days a month.
Here are some items, I just cannot cook without.
Casserole Dishes and Small Roasting Pans – These are items you will probably use a lot. If you don’t already own several, look for them at garage sales, or watch for sales. The disposable kind are great, because you do not have to throw them out after one use, they can be reused several times, and the food can be frozen or cooked, right in them.
Baking Dishes – You will probably need some baking dishes of various sizes to make or prepare different parts of your meals.
Frying Pans and Skillets – These are indispensable. I recommend having several large skillets and pans available on the day of your session. Yes, you might only have four burners, but you might wish to move one right off, and put another right on, and this eliminates the time taken to figure out where to put whatever was in the pan before.
Large Stock Pots – Probably my favorite items for the day of my cooking sessions. We have three, and sometimes I borrow from others. You can make entire meals in these large pots and they can go right into storage bags and into the freezer. Sauces, soups, stews, pastas, and more can be made in large batches.
Pie Plates and Pans – If you plan to make any type of pot pies or even regular fruit pies, to freeze, you will need several. Many people forget that desserts can be made using this method as well.
Set of Sharp Knives – Although, you might not actually need them, they are extremely handy to have around. Makes slicing and dicing a bit easier. If you have a hand held chopper or a like minded counterpart, you will do well.