or place it on a cookie sheet. You can bake in some of those cardboard pans too but you need to check the temperature on the container as some only go so high.

Make sure it is not too heavy, as another poster already advised.

Those aluminum containers are too thin to be stable especially with a casserole that has a lot of moisture. I've also used the cardboard ones, same deal, put on a baking sheet.

I would NOT cook a lasagna or any tomato based recipe in one of the aluminum ones, especially if it will be stored in it - the tomato will eat the aluminum! I just thawed and used an eggplant lasagna that I cooked in one of the cardboard containers and that worked well. The supplied plastic lid wouldn't stay on so I covered it with plastic wrap then foil for freezing.

I've spent the last 6 months working in an Italian restaurant and we've prepared virtually every take-out entree for the oven in those: baked ziti, chicken parm, eggplant rollatini, chicken cacciatore, lasagna, etc. The tomatoes have never effected the aluminum pan...it might if you left it for a week-plus but we've stored things in them for even 3-5 days with zero degradation.

Eggs OTOH I wouldn't leave in an aluminum container.

By the time I take the casserole out of the freezer, reheat and use the rest of the dish. Tomato sauce will eat through aluminum foil faster, overnight in some cases.

Maybe the stuff sold for restaurant use is better quality, but the cheap pans I've bought at the grocery just don't hold up.

I will remember that hint!

..as the walls of those containers are much thinner than a casserole dish.

Not only can you, it's what it's actually designed for...the intention of its design is to allow restaurants to prepare meals for the oven in the same 100% recyclable (both plastic lid and aluminum pan. Don't put the plastic lid in the oven or microwave) take-out container that they are served in, thus reducing both waste and clean-up. I've probably prepared 100 chicken Parmesan dinners in the past 5 months in them. Half that in baked ziti casseroles.

It does reduce the cook-time substantially however as another poster said. Also, if you're not experienced in handling them and removing them from the oven, I would set it on a firmer pan...that pan will remain clean so it doesn't need to be washed, it's there to support the bottom and make it easier to remove the foil-pan from the oven.

oil so that it doesn't stick.

You can also line it with parchment /baking paper for easier removal, if it's a stiff type casserole.

Handy tip; when using parchment or baking paper, take the size you need and crumple it up under running water for a moment. Squeeze it tight after, as small as you can. Then uncrumple it, (step outside) and shake it back out flat, really hard to get rid of the rest of the moisture.

It will then fit very easily into any shape pan you're using it in. No cutting, folding or slipping.