Spray a large skillet with non-stick cooking spray. Over medium-high heat cook sausage links with casings removed (see recipe video for how to remove casings), breaking up meat with a spoon. Cook until brown and cooked through, about 5 minutes.
To the skillet add marinara and water. Bring to boil, then add uncooked lasagna noodles. Lower heat to a simmer, cover, and cook until lasagna noodles are cooked al dente, about 15 minutes.
Remove cover and add spinach. Stir spinach into sauce until it all wilts. Stir in parmesan cheese and ricotta.
Immediately top skillet lasagna with mozzarella. Cover with lid, turn off heat, and let sit for a few minutes, or until cheese is melted. Alternatively, if using an oven safe pan, place skillet under broiler for 1-2 minutes to melt cheese. Garnish with basil.
To Make Skillet Lasagna Vegetarian:
Instead of using Italian sausage, substitute 2-3 cups of chopped veggies, such as mushrooms, onions, or peppers. Sauté in a splash of olive oil until tender, then season with salt and pepper.
Add the marinara and water and bring to a boil. Add noodles, cover, and lower heat to a simmer. Cook for 15 minutes, or until noodles are al dente.
Increase spinach to 6 cups and finish the recipe as written with ricotta, parmesan, and mozzarella.