Baked Sausage, Spinach, and Ricotta Stuffed Shells

Why You’ll Love This Recipe

• Comforting Italian flavors with creamy ricotta, savory sausage, and bright marinara.
• Family-friendly, make-ahead friendly, and freezer-friendly.
• Golden, bubbly mozzarella top with irresistible browned edges.
• Clear steps and exact measurements for stress-free success.

Grocery List

• Produce: 1 small yellow onion, 3 garlic cloves, 10 oz frozen chopped spinach, fresh basil or parsley
• Dairy: Whole-milk ricotta (15 oz), shredded low-moisture mozzarella (about 3 cups/12 oz), grated Parmesan (3/4 cup total), 1 large egg
• Pantry: Jumbo pasta shells, marinara sauce (at least 3 1/2 cups), olive oil, kosher salt, black pepper, Italian seasoning, red pepper flakes, ground nutmeg, aluminum foil

Full Ingredients

For the shells and sauce

• 30 jumbo pasta shells (cook 26; you will fill ~24)
• 3 1/2 cups (828 ml) marinara sauce, divided
• 1 tbsp kosher salt (for pasta water)
• 1 tsp olive oil (to prevent sticking after boiling)

For the sausage–spinach ricotta filling

• 1 tbsp olive oil
• 1 small yellow onion, finely diced (about 1/2 cup/75 g)
• 3 garlic cloves, minced
• 1 lb (450 g) Italian sausage (mild or hot), casings removed
• 10 oz (285 g) frozen chopped spinach, thawed and squeezed very dry
• 15 oz (425 g) whole-milk ricotta
• 1 large egg
• 1 cup (4 oz/113 g) shredded low-moisture mozzarella
• 1/2 cup (1.5 oz/45 g) finely grated Parmesan
• 1 tsp dried Italian seasoning
• 1/2 tsp freshly ground black pepper
• 1/4 tsp red pepper flakes (optional for heat)
• 1/8 tsp ground nutmeg
• 3/4 tsp kosher salt

For topping and garnish

• 1 1/2–2 cups (6–8 oz/170–226 g) shredded low-moisture mozzarella
• 1/4 cup (22 g) finely grated Parmesan
• 2 tbsp chopped fresh basil or flat-leaf parsley

Step-by-Step Instructions

Step 1: Preheat and boil the shells

Preheat the oven to 375°F (190°C) with a rack in the center. Bring a large pot (5–6 quarts) of water to a boil and add 1 tablespoon kosher salt. Cook 26–30 jumbo shells until very al dente, about 1–2 minutes less than package directions (typically 8–9 minutes). Drain, rinse under cool water to stop cooking, and toss with 1 teaspoon olive oil so they do not stick. Set aside in a single layer on a sheet pan.

Step 2: Sauté aromatics and brown the sausage

Heat 1 tablespoon olive oil in a large skillet over medium heat. Add the diced onion and cook until tender and translucent, 3–4 minutes. Stir in the minced garlic and cook 30 seconds until fragrant. Add the sausage, breaking it up with a spoon, and cook until browned and cooked through, 6–8 minutes. Drain excess fat and let the mixture cool for 5 minutes so it does not melt the cheeses or cook the egg in the filling.

Step 3: Mix the creamy ricotta filling

In a large bowl, combine ricotta, egg, 1 cup mozzarella, 1/2 cup Parmesan, Italian seasoning, black pepper, red pepper flakes, nutmeg, and 3/4 teaspoon kosher salt. Squeeze the thawed spinach completely dry (really wring it out) and fold it into the ricotta mixture along with the cooled sausage-onion mixture until evenly combined.

Step 4: Sauce the pan and fill the shells

Spread 1 cup of marinara sauce into the bottom of a 9×13-inch (3-quart) baking dish. Using a spoon or a piping bag, fill about 24 shells with roughly 2 heaping tablespoons of filling each (about 45–50 g). Nestle the stuffed shells, open side up, into the sauced baking dish in tight rows.

Step 5: Blanket with marinara and cheese

Spoon the remaining 2 1/2 cups marinara evenly over the shells, leaving some ridges peeking through. Sprinkle with 1 1/2–2 cups shredded mozzarella and 1/4 cup Parmesan for a bubbly, browned top.

Step 6: Bake until bubbling and golden

Cover the dish tightly with foil (spritz the underside with nonstick spray so cheese does not stick) and bake for 20 minutes. Remove the foil and bake another 12–15 minutes, until the sauce is bubbling around the edges and the cheese is melted. For extra browning, broil for 1–2 minutes, watching closely.

Step 7: Rest, garnish, and serve

Let the shells rest for 10 minutes so the filling sets slightly and slices cleanly. Scatter chopped basil or parsley over the top. Serve warm, with extra warm marinara on the side if you like.

Pro Tips

• Undercook the shells by 1–2 minutes; they finish in the oven and hold their shape better for filling.
• Squeeze the spinach completely dry to avoid a watery filling. A clean kitchen towel works best.
• Let the sausage mixture cool before mixing with ricotta so the egg does not curdle.
• For neat, quick filling, use a large piping bag or a zip-top bag with a 3/4-inch corner snipped off.
• Resting 10 minutes after baking helps the stuffed shells set and makes serving easier.

Variations

• Vegetarian: Skip the sausage and sauté 10 oz cremini mushrooms with the onion, or double the spinach. Add an extra 1/2 cup grated Parmesan for savory depth.
• Lighter: Use turkey or chicken Italian sausage and part-skim ricotta and mozzarella.
• Spicy arrabbiata: Swap marinara for spicy arrabbiata and bump red pepper flakes to 1/2 teaspoon.

Storage & Make-Ahead

Refrigerate leftovers in an airtight container for up to 4 days. Reheat covered at 350°F (175°C) for 20–25 minutes, or until hot. To make ahead, assemble up to the baking step, cover tightly, and refrigerate up to 24 hours. Add 5–10 minutes to the bake time if cold. To freeze, assemble in a freezer-safe dish, wrap well, and freeze up to 2 months. Bake from frozen at 375°F (190°C) covered for 40–45 minutes, then uncover and bake 15–20 minutes until hot and bubbly.

Nutrition (per serving)

Approximate values per serving (4 shells): 640 calories; 32 g fat (14 g saturated); 45 g carbohydrates; 5 g fiber; 10 g sugar; 38 g protein; 1,300 mg sodium. Values will vary based on brands and exact measurements.