Creamy Seafood Lasagna with Spinach and Alfredo

Why You’ll Love This Recipe

• Restaurant-quality seafood lasagna with a plush, garlicky Alfredo that stays creamy—not greasy.
• No-boil noodles make assembly easy and foolproof.
• Balanced filling: succulent shrimp, sweet scallops, and buttery crab with bright lemon and spinach.
• A bronzed Parmesan–mozzarella cap that bakes up bubbly with irresistible crispy edges.

Grocery List

• Produce: 1 head garlic, 1 lemon, 1 small bunch parsley, small bunch basil (optional), 10 oz frozen chopped spinach
• Dairy: Whole-milk ricotta (24 oz), whole milk, heavy cream, Parmesan, low-moisture mozzarella, 1 large egg, unsalted butter
• Pantry: No-boil lasagna noodles, olive oil, all-purpose flour, kosher salt, black pepper, nutmeg, Old Bay or paprika (optional), Seafood: large shrimp, bay or sea scallops, lump crabmeat

Full Ingredients

Seafood

• 1 lb large shrimp (16–20 count), peeled and deveined
• 8 oz bay scallops (or 8 oz sea scallops, cut into 3/4-inch pieces)
• 8 oz lump crabmeat, picked over for shells
• 1 tbsp olive oil
• 1/2 tsp kosher salt, plus more to taste
• 1/4 tsp freshly ground black pepper
• 1/2 tsp Old Bay seasoning or sweet paprika (optional)

Garlicky Alfredo Sauce

• 6 tbsp unsalted butter
• 6 garlic cloves, minced
• 1/4 cup all-purpose flour
• 2 cups whole milk
• 1 1/2 cups heavy cream
• 1 cup finely grated Parmesan cheese
• 1 tsp finely grated lemon zest
• 2 tsp fresh lemon juice
• 1/8 tsp grated nutmeg
• 1 tsp kosher salt (adjust to taste)
• 1/2 tsp freshly ground black pepper

Ricotta–Spinach Layer

• 24 oz whole-milk ricotta cheese
• 10 oz frozen chopped spinach, thawed and squeezed completely dry
• 1 large egg
• 1/2 cup grated Parmesan
• 2 tbsp finely chopped fresh parsley
• 1/2 tsp kosher salt
• 1/4 tsp black pepper

Pasta, Cheeses & Finish

• 12 sheets no-boil lasagna noodles (more if your brand is smaller; see notes)
• 3 cups shredded low-moisture mozzarella (about 12 oz)
• 1/2 cup grated Parmesan (for the top)
• Extra chopped parsley or basil, and additional lemon zest, for garnish
• Up to 1/2 cup hot water to loosen sauce if needed
• Nonstick spray or a little butter for the baking dish

Step-by-Step Instructions

Step 1: Prep and preheat

Heat oven to 375°F (190°C). Lightly grease a 9×13-inch baking dish with nonstick spray or butter. Thaw the spinach and squeeze it in a clean kitchen towel until absolutely dry—this prevents a watery lasagna. Pat the shrimp and scallops dry with paper towels and season with 1/2 tsp salt, 1/4 tsp pepper, and Old Bay or paprika if using.

Step 2: Make the garlicky Alfredo

In a medium saucepan over medium heat, melt the butter. Add garlic and cook 60 seconds until fragrant. Sprinkle in the flour and whisk for 1 minute. Slowly whisk in the milk, then the cream, until smooth. Bring to a gentle simmer and cook 4–6 minutes, whisking often, until the sauce thickly coats a spoon. Remove from heat and stir in 1 cup Parmesan, lemon zest, lemon juice, nutmeg, 1 tsp salt, and 1/2 tsp pepper. Taste and adjust seasoning. You should have about 4 cups of sauce. Set aside.

Step 3: Sear the seafood

Heat a large skillet over medium-high and add olive oil. Sear shrimp 1–2 minutes per side until just opaque; transfer to a bowl. Sear scallops 1–2 minutes total until barely firm; add to the shrimp. Gently fold in the crab. Pour 2 1/2 cups of the Alfredo over the seafood and fold to coat. Reserve the remaining ~1 1/2 cups Alfredo for assembly and topping.

Step 4: Mix the ricotta–spinach layer

In a bowl, combine ricotta, squeezed-dry spinach, egg, 1/2 cup Parmesan, parsley, 1/2 tsp salt, and 1/4 tsp pepper. Stir until evenly green and creamy.

Step 5: Start layering

Spread 1/2 cup of the reserved Alfredo in the bottom of the baking dish. Add a single layer of no-boil noodles (slightly overlapping if needed). Dollop and spread 1/3 of the ricotta mixture over the noodles. Spoon 1/3 of the seafood Alfredo over the ricotta. Sprinkle with 1/2 cup mozzarella.

Step 6: Repeat layers

Repeat the noodle, ricotta, seafood, and mozzarella sequence two more times (for three interior layers total). Top with a final layer of noodles. If the reserved Alfredo is very thick, whisk in up to 1/2 cup hot water until pourable. Spread all remaining reserved Alfredo over the top, edge to edge, so the noodles are fully covered.

Step 7: Add the Parmesan–mozzarella cap and bake

Sprinkle the top with 1 1/2 cups mozzarella and 1/2 cup Parmesan. Cover the dish tightly with foil sprayed on the underside (to prevent sticking). Bake at 375°F for 35 minutes. Uncover and bake 12–15 minutes more until the top is bubbling and nicely golden. For extra color, broil 1–2 minutes, watching closely.

Step 8: Rest, garnish, and serve

Let the lasagna rest 15 minutes to set clean slices. Finish with chopped parsley or basil and a little fresh lemon zest. Slice and serve warm.

Pro Tips

• Keep the Alfredo slightly loose—no-boil noodles need moisture to soften properly.
• Pat seafood very dry and undercook slightly on the stovetop; it will finish in the oven.
• Squeeze spinach until no liquid drips; excess moisture can make layers soupy.
• Spray the foil so the cheese cap doesn’t stick, and cover fully so edges don’t dry out.
• Letting the lasagna rest 15 minutes ensures neat slices and a creamy, not runny, interior.

Variations

• Cajun Kick: Toss seafood with 1–2 tsp Cajun seasoning and add a pinch of cayenne to the Alfredo.
• Lobster & Fennel: Swap crab for 8 oz lobster meat and sauté 1/2 cup thinly sliced fennel with the garlic.
• Lighter Spin: Use part-skim ricotta, half-and-half instead of cream, and add 8 oz sautéed mushrooms for bulk.

Storage & Make-Ahead

Assemble up to 24 hours ahead, cover, and refrigerate. Bake from cold at 375°F for 55–60 minutes (uncover for the last 15 minutes). Leftovers keep 2–3 days in the refrigerator; reheat covered at 350°F for 20–25 minutes until warmed through. For longer storage, cool completely, slice, wrap tightly, and freeze up to 2 months. Reheat from frozen at 350°F, covered, 40–50 minutes. Note: seafood is best within a couple of days for peak texture.

Nutrition (per serving)

Approximate per serving (1/10 of pan): 730 calories; 46 g protein; 34 g carbohydrates; 44 g fat; 2 g fiber; 1180 mg sodium. Values will vary by brands and exact seafood.