The first step is to prepare the meat. If you opt for ground beef, you'll need to brown, drain, and season it to taste. Rotisserie chicken, leftover chicken, or leftover ham works great. Buying a slice or chunk of cooked ham is an easy option. Simply cut it into cubes and toss it in with the rest of the ingredients. We're looking for at least 2 cups of cooked and seasoned meat. Feel free to add extra if desired.
2 cups cooked and seasoned meat (cooked and cut up chicken, cubed ham, or browned and crumbled hamburger)
In a large bowl, combine the cooked and seasoned meat, milk, cream of mushroom soup, uncooked macaroni, shredded cheese or cubed Velveeta, chopped onion, green peas, and black pepper.
2 cups milk, 2 cups macaroni (uncooked), 2 (10.5 oz.) cans cream of mushroom soup, 2 cups shredded cheese (or cubed Velveeta), approx. 1/4 cup onion (chopped), 1 cup green peas, 1/2 teaspoon black pepper
Blend well, making sure that all ingredients are well-mixed, coating the macaroni evenly with the creamy mixture.
Pour the mixture into a greased 9x13" baking dish, spreading it out evenly.
Cover the dish tightly with foil and refrigerate it overnight.
Place the covered baking dish in the oven and bake at 350℉ for about an hour or until the casserole is heated through and the macaroni is tender.
Allow the casserole to cool for a few minutes before serving. Stir, scoop out generous portions, and enjoy!
Cool, refrigerate, and reheat any leftovers.