Who doesn't love stuffed pasta shells? This Easy Lasagna Stuffed Shells is filled with beef, ricotta cheese, and is topped with even more cheese. This freezer-friendly pasta bake is always a crowd-pleaser.
In a skillet, brown the beef, seasoning with salt and pepper. Once 80% browned, add in diced onions, minced garlic, and diced mushrooms. Sauté for 2-3 minutes.
Add in ¾ cup marinara sauce, tomato paste, and baby spinach. Simmer for 10 minutes. Stirring throughout.
Add in the jumbo pasta shells to the boiling water and cook for 1 minute before it’s al dente (my package says it takes 10 minutes to cook, so I cooked mine for 9 minutes, yours may vary).
Meanwhile, in a large bowl, combine the ricotta cheese, mozzarella, parmesan, egg, and dried basil. Mix to combine.
Drain the water from the pasta when done.
Once the sauce and beef has done simmering, add it to the cheese mixture. Stir to combine.
In a 12¼ by 8¼ baking dish, spray with some non-stick and then spread 1 cup of marinara sauce on the bottom.
Stuff each shell with the cheesy beef mixture and place them in the baking dish.
Add any extra cheesy beef mixture you have on top of the shells, the rest of the marinara sauce, and top with the rest of your mozzarella.
Place the beef stuffed shells casserole onto the bottom rack of the oven and bake for 30 minutes.