Baked Conchiglie with Spinach and Three Cheeses
Jumbo pasta shells stuffed with a creamy blend of ricotta, mozzarella, and Parmesan, nestled in marinara sauce and spinach, then baked until bubbly and golden. A comforting, vegetarian-friendly Italian-American classic that serves as both a weeknight dinner and an impressive dish for guests.
- Prep
- 25 min
- Cook
- 35 min
- Wait
- 15 min
- Total
- 1 hr 15 min
- Makes
- 6 servings (about 18–20 shells per person)
Steps
Before you start
- Preheat your oven to 375 °F (190 °C)
- Cook the pasta according to package directions until just al dente (shells will cook further in the oven); drain and set aside on a baking sheet so they don't stick
- Have all cheeses measured and spinach squeezed dry before you start filling
Make the cheese filling
- In a large mixing bowl, combine ricotta, 6 oz (170 g) of the shredded mozzarella, ½ cup (50 g) of the Parmesan, the squeezed spinach, minced garlic, egg, nutmeg, and a pinch of salt and black pepper.
- Stir until evenly blended and no streaks of cheese remain.
- Taste and adjust seasoning if needed.
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Ready when: Filling is creamy and well combined with no streaks
Tip: Squeeze the spinach very thoroughly—excess moisture will dilute the filling and make the pasta soggy during baking.
Spread sauce in baking dish
- Pour ½ cup (120 ml) of the marinara sauce into the bottom of a 9×13-inch (23×33 cm) baking dish.
- Spread it evenly with a spatula or the back of a spoon.
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Ready when: Bottom is completely covered
Fill the pasta shells
- Using a small spoon (a ½-tsp measuring spoon or demitasse spoon works well), fill each cooked shell with about 1½ to 2 teaspoons of the cheese filling.
- Don't overstuff; the filling should sit level with the rim of the shell, not overflowing.
- Arrange filled shells in the baking dish in a single layer, open-side up if possible.
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Ready when: All shells are filled and arranged in a single layer
Tip: If some shells crack during handling, use them as 'patches' to cover damage on other shells, or save them for the next batch. Work gently so they don't break further.
Cover with remaining sauce and cheese
- Pour the remaining marinara sauce (about 1⅓ cups/320 ml) evenly over the filled shells.
- Scatter the remaining 2 oz (55 g) shredded mozzarella and ¼ cup (25 g) Parmesan over the top.
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Ready when: Sauce covers all shells; cheese is sprinkled evenly on top
Bake until bubbling and goldenOven 375°F / 190°C
- Cover the baking dish loosely with aluminum foil (tent it so it doesn't stick to the cheese).
- Place on the center oven rack and bake at 375 °F (190 °C) for 25 minutes.
- Remove the foil and bake uncovered for a further 10 minutes, until the cheese on top is melted, lightly golden, and the sauce is bubbling around the edges.
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Ready when: Cheese is golden and sauce is bubbling vigorously at the edges
Tip: Don't skip the foil—it prevents the top from browning too quickly before the filling heats through. If you prefer a darker, crispier top, remove foil 5 minutes earlier.
Rest and serve
- Let the baked conchiglie rest for 5 minutes out of the oven.
- This allows the sauce to set slightly and makes scooping easier.
- Serve warm with extra grated Parmesan and crusty bread on the side.
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Ready when: Steam has subsided slightly
Good to know
Tips
- Squeeze the thawed spinach really well—a salad spinner or clean kitchen towel works better than your hands alone. Excess moisture will pool in the filling and make the shells and sauce watery.
- Slightly undercook the conchiglie by 1 minute when boiling it. It will finish cooking in the oven, and you want shells that hold their shape and don't turn mushy.
- Don't skip the resting period; it allows the sauce to firm up slightly and makes serving neater. It also gives you a few minutes to set the table or pour drinks.
- For a lighter dish, use part-skim ricotta and low-fat mozzarella, and use fresh spinach instead of frozen. The result will be less creamy but still satisfying, and significantly lower in fat and calories.
Make ahead
You can fill and assemble the entire baking dish up to 4 hours ahead. Cover tightly with plastic wrap and refrigerate. Bake directly from the fridge, adding 5–10 minutes to the covered baking time.
Storage & reheating
Refrigerate leftovers in an airtight container for up to 3 days. To reheat, cover with foil and warm in a 325 °F (163 °C) oven for 15–20 minutes, or transfer a portion to a microwave-safe dish, cover loosely, and microwave at 50% power for 2–3 minutes, stirring once. Do not freeze; the texture of the ricotta breaks down on thawing.
Substitutions
- frozen spinach → 2 cups (60 g) packed fresh baby spinach, coarsely chopped and sautéed in 1 tsp olive oil until wilted, then squeezed dry. Fresh spinach offers a slightly brighter flavor and lighter texture; you'll need about ¼ the weight of frozen because fresh spinach shrinks dramatically.
- marinara sauce (store-bought or homemade) → 2 cups (480 ml) homemade tomato sauce (or a combination of canned crushed tomatoes, tomato paste, garlic, herbs, and olive oil). Use a good-quality sauce; it forms the flavor base for the dish. Avoid overly thin or watery sauces.
- shredded low-moisture mozzarella cheese → 8 oz (225 g) fresh mozzarella, torn into bite-sized pieces and drained well on paper towels. Fresh mozzarella creates a creamy, pillowy texture but may release extra liquid; pat pieces dry before using to prevent a watery dish.
- whole-milk ricotta cheese → 1 cup (240 g) mascarpone combined with ¼ cup (60 ml) heavy cream and 1 tbsp (15 ml) lemon juice. This creates a richer, silkier filling; the acid balances the richness and prevents the cheese from tasting one-dimensional.
