1 teaspoon olive oil
1 onion, small dice
2 pounds lean ground beef
3 cloves garlic, minced
1 tablespoon dried Italian seasoning
1/2 teaspoon salt
1/4 teaspoon ground black pepper
1 pre-made roll polenta, sliced into 1/2-inch rounds
2 cups mozzarella cheese
4 cups spaghetti sauce
1/2 cup Parmesan cheese, grated
Preheat oven to 350 F and grease a 9-by-13 casserole dish.
Heat olive oil in a large frying pan set over medium heat. When hot, add onion and cook for about 3 minutes, until soft and translucent.
Add ground beef, breaking it up as you do. Cook beef for about 8 minutes, until no longer pink.
Add garlic, Italian seasoning, salt, and pepper to the pan. Stir and cook for one more minute.
Add polenta slices to the bottom of the pan, just enough to cover.
Spread 1/2 of the meat mixture over the polenta slices.
Sprinkle 1/3 of the mozzarella cheese over the meat mixture.
Spread 1/3 of the spaghetti sauce over the mozzarella cheese.
Repeat layers one time, ending with a last layer of polenta rounds.
Spread remaining spaghetti sauce over the top polenta rounds.
Sprinkle remaining mozzarella cheese over the polenta and top with Parmesan cheese.
Place in the preheated oven and cook for about 30 minutes, until cheese is fully melted and the casserole is bubbling throughout.