Mix all ingredients together in a large bowl. (You will want an extra large bowl for this one!)
Pour everything into a 9x13 casserole dish, scraping the sides well to get all the casserole ingredients out.
Using a large spoon or spatula, press casserole into dish so everything is tightly packed.
Bake uncovered on the center oven rack at 350 degrees for 30 - 45 minutes, or until casserole is heated through and top is browned to your liking.
This is a great recipe to use up leftover corned beef from the holidays, or if you want it on a random Tuesday in February, hit the deli for some sliced corned beef!
If you are unable to locate corned beef, Pastrami has a very similar flavor and can be substituted.
If you are unable to locate Russian dressing, Catalina dressing has a very similar flavor and can be substituted.
It is always preferably to use freshly shredded cheese as opposed to pre-shredded because pre-shredded cheese contains anti-caking ingredients that can inhibit melting. That said, this recipe will still work with pre-shredded cheese.
Calories are automatically generated. For best results calculate based on your exact ingredients.