Sealing large items for the freezer
My question is about sealing a large item such as a lasagna or a pie for the freezer.
I would like to freeze a whole pie or lasagna in its dish ready for baking. Usually I freeze things inside freezer bags or in plastic containers, but the largest freezer bags I have are 1 gallon, which isn't big enough to hold most round pie plates, never mind a lasagna.
I have read that covering the dish with plastic wrap and then foil will work, but does this really keep the freezer burn out? Is it possible to buy giant freezer bags that will fit a 9x13 baking dish? Has anyone tried those pyrex dishes with the sealing lids in the freezer?
Ideas that don't involve wasting huge quantities of wrapping material are a plus.