Yes, you can successfully freeze hamburger tater tot casserole! In fact, this recipe is the freezer meal of all freezer meals! The go-to recipe most home cooks use when they first explore the world of freezer cooking. Unlike other recipes, a tater tot casserole retains both its texture and flavor once frozen. And, good news. No need to alter the recipe for a frozen version. Simply follow the recipe as written, then wait to bake the finished casserole until it is time to serve. Tightly cover the pan first with plastic wrap, then aluminum foil. Doing this keeps the tater tot casserole fresh for 4-5 months in the freezer. To keep your favorite 9x13 baking dish free from the freezer, be sure to grab some quality aluminum pans with lids to use instead. Don't go for the cheap ones or you'll end up with tater tot casserole all over the floor. When it is time to bake the casserole, remove the plastic and foil from the pan and bake at 350 degrees for 60 minutes. Or, thaw it for a few days in the refrigerator before baking, adding about 10 extra minutes to compensate for the cold temperature of the ingredients.