Prepare the Marinara Sauce Recipe or use one jar of store bought sauce
Boil the pasta based on the manufacturer’s instructions for the shortest
amount of time recommended. Drain and rinse the pasta with cold water
Preheat oven to 350F
In a large skillet over high heat, add olive oil and onions, sauté for 3
minutes until soft, add the garlic for 20 seconds, add the chopped
mushrooms, stir to combine, cover and let steam for 5 minutes
Remove cover, stir and continue to sauté until the mushrooms have released all their moisture and are nicely browned
Remove from the heat, add 1 Cup of Marinara sauce and stir to combine,
place the chopped spinach on top of the hot mushrooms and cover, let the
spinach wilt
Add the ricotta and parmesan cheeses to the mushroom and spinach stuffing and stir to combine
Add a small amount of Marinara sauce to the bottom of an 8 x 12-inch casserole dish and spread to cover the bottom
Gently spoon the spinach and mushroom stuffing into shells and line them
up in the casserole dish, any leftover stuffing can be dolloped in and
around the stuffed shells, no one will complain
Evenly spoon the remaining Marinara sauce over the stuffed shells
Evenly distribute the mozzarella cheese over the top of the stuffed shells
Bake for approximately 30-40 minutes, or until the mozzarella cheese is nicely browned and the sauce is bubbling