Spinach Stuffed Shells

You can prepare these delicious cheesy vegetarian stuffed shells using either fresh or frozen spinach, whatever is easier for you.
Serves 4 to 6
Makes approximately 20 stuffed shells
Prep 35 minutes
Cook 33 to 36 minutes
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These cheesy stuffed shells represent the ultimate comfort food experience. Filled with a luxurious mix of ricotta and mozzarella cheese combined with sautéed spinach and garlic, they are baked in marinara sauce topped with melted cheese. Pair them with a simple green salad and your preferred Italian red wine for a meal that’s certain to please.

What’s the Difference Between Stuffed Shells and Manicotti?

Although both stuffed shells and manicotti are Italian pastas filled with cheese, they do have some differences.

Stuffed Shells:

Jumbo pasta shells are partially boiled, then filled with cheese (typically ricotta and mozzarella). Spinach (as used in this recipe) or ground beef can be included as well. The shells are arranged in a baking dish, smothered with tomato sauce and cheese, and baked.

Manicotti:

Instead of shells, long pasta tubes known as manicotti are partially boiled and filled. The fillings, tomato sauce, and cheese topping are the same as used for stuffed shells.

Can I Use Frozen Spinach?

Definitely, you can use frozen spinach for these stuffed shells. This recipe allows for either fresh or frozen spinach based on your preference.
To prepare frozen spinach, thaw it following the directions on the package, place it on a clean kitchen towel, roll it up, and squeeze to remove excess liquid. After this, add it to the skillet with sautéed garlic and red pepper flakes to warm it and remove any remaining moisture.

Can I Freeze Stuffed Shells?

Absolutely! Stuffed shells freeze very well. It’s best to freeze them before baking, as cooking them first, then freezing and reheating may result in dryness. Arrange the shells in a baking dish or aluminum pan, cover them with sauce and cheese, then seal the dish tightly with aluminum foil and place it in the freezer for up to two months.
To bake the frozen shells, move the baking dish to the refrigerator the night before you plan to eat to defrost gradually. Once thawed, cover with aluminum foil and bake at 375°F for 20 minutes, then uncover and bake until the cheese melts and the sauce bubbles, about another 10 minutes.

Spinach Stuffed Shells Recipe

Prep time 35 minutes
Cook time 33 to 36 minutes
Makes approximately 20 stuffed shells
Serves 4 to 6

Ingredients

• 10 ounces baby spinach (around 10 cups) or 1 (10ounce) packet frozen chopped spinach
• 3 garlic cloves
• 12 ounces lowmoisture wholemilk or partskim mozzarella cheese, grated (about 3 cups)
• 1 ounce Parmesan cheese, finely grated (about 1/2 tightly packed cup grated on a Microplane or 1/3 cup
• bought
• 3 tablespoons olive oil, divided
• 1/4 teaspoon red pepper flakes
• 3/4 teaspoon kosher salt, divided, plus extra for the water used for pasta
• 6 ounces of dried jumbo pasta shells (approximately 20)
• 1 (15 to 16ounce) container wholemilk ricotta cheese (around 2 heaping cups)
• 1/4 teaspoon fresh ground black pepper
• 1 (approximately 24ounce) jar of marinara sauce (3 cups), split

Instructions

1. Position a rack in the upper third of the oven and preheat it to 375°F.
2. If you have frozen spinach, defrost 10 ounces according to the directions on the package. Place it in a clean kitchen towel, roll it up, and squeeze to remove as much moisture as possible.
3. Chop 3 garlic cloves finely. Use a box grater to shred 12 ounces of lowmoisture mozzarella cheese on the larger holes (this is around 3 cups). Grate 1 ounce of Parmesan cheese finely (approximately 1/2 packed cup).
4. Bring a sizable pot with salty water to a boil. At the same time, warm 2 tablespoons of olive oil in a large, deep skillet over medium heat until it shimmers. Add the minced garlic and 1/4 teaspoon of red pepper flakes, cooking for about 1 minute until it smells good. If you are using fresh baby spinach, put in 10 ounces in small handfuls, stirring until it wilts slightly, for about 5 minutes. If you have frozen spinach, add it to the skillet and stir occasionally until the moisture is gone, which takes about 2 minutes. Season it with 1/4 teaspoon kosher salt. Remove from the heat and allow it to cool a bit while you parboil the shells.
5. Put 6 ounces of jumbo pasta shells into the boiling water and cook them until they are slightly firm, which takes roughly 9 minutes, or follow package instructions. Drain them, then drizzle with the leftover 1 tablespoon of olive oil while still in the strainer and mix well.
6. Combine 15 to 16 ounces of ricotta cheese, 1 cup of mozzarella, the remaining 1/2 teaspoon kosher salt, and 1/4 teaspoon black pepper in the pan of spinach and mix it all together.
7. Spread 1 cup of marinara sauce from the 24ounce jar into a 9x13inch baking dish. Fill each shell with a generous spoonful (about one heaping tablespoon) of the ricotta blend and arrange them fillingside up in the dish. Pour the rest of the 2 cups of marinara sauce over the shells and top with the remaining 2 cups of mozzarella and Parmesan cheese.
8. Bake uncovered until the cheese is melted and the sauce bubbles, which should take around 30 minutes. Allow it to cool on a wire rack for 5 minutes before serving.

Recipe Notes

Make it ahead:

You can prepare the shells and keep them, unbaked, in the fridge for up to 2 days, or freeze them for 1 month. When you are ready to bake frozen shells, thaw them in the refrigerator overnight.
Bake them covered with aluminum foil at 375°F for 20 minutes, then uncover and continue to bake until the cheese is melted and the sauce bubbles, about another 10 minutes.

Storage:

You can keep leftovers in an airtight container in the refrigerator for as long as 4 days.