If you’re craving a rich, comforting dinner without the extra carbohydrates, this Creamy Seafood, Spinach and Mushroom Low-Carb Bake is a delicious choice. Made with tender seafood, fresh spinach, earthy mushrooms, a creamy garlic sauce, and melted cheese, this satisfying casserole brings restaurant-style flavor straight to your kitchen.
This easy seafood bake combines simple ingredients into a warm, creamy dish that works beautifully for busy weeknight dinners, relaxed family meals, or special occasions. The seafood adds a delicate, savory flavor, while the spinach and mushrooms provide color, texture, and extra goodness. A generous layer of cheese creates a golden, bubbly topping that makes every serving irresistible.
Best of all, this recipe skips traditional pasta, rice, and breadcrumbs, making it suitable for many low-carb meal plans. Serve it on its own or alongside roasted vegetables for a comforting meal that feels indulgent without relying on starchy ingredients.
Why You’ll Love This Low-Carb Seafood Bake
Rich and creamy: Cream cheese, heavy cream, garlic, and melted cheese combine to create a smooth, flavorful sauce.
Packed with seafood: Shrimp and other seafood bring a delicious, savory taste to every bite.
Loaded with vegetables: Spinach and mushrooms add texture, color, and flavor without needing pasta or rice.
Easy to prepare: The ingredients come together in a baking dish, making this a practical option for weeknight cooking.
Naturally low in carbohydrates: The recipe avoids traditional casserole fillers such as potatoes, pasta, and breadcrumbs. Exact carbohydrate content depends on the ingredients and portion size.
Easy to customize: You can use your favorite seafood, adjust the seasonings, or add different cheeses to suit your preferences.
Ingredients for Creamy Seafood, Spinach and Mushroom Low-Carb Bake
This recipe serves approximately 4 people.
For the Seafood and Vegetables
- 1 pound shrimp, peeled and deveined
- 8 ounces mushrooms, sliced
- 4 cups fresh spinach
- 2 tablespoons butter
- 3 cloves garlic, minced
- 1 tablespoon olive oil
- 1/2 teaspoon salt, or to taste
- 1/2 teaspoon black pepper
- 1/2 teaspoon paprika
- 1/4 teaspoon red pepper flakes, optional
For the Creamy Sauce
- 4 ounces cream cheese, softened
- 1/2 cup heavy cream
- 1/2 cup sour cream
- 1 cup shredded mozzarella cheese, divided
- 1/2 cup grated Parmesan cheese
- 1 teaspoon Italian seasoning
- 1 teaspoon lemon juice
- 1/4 teaspoon onion powder
Optional Garnish
- 1 tablespoon chopped fresh parsley
- A few lemon wedges
- Extra grated Parmesan cheese
Seafood options: You can replace some of the shrimp with scallops, cooked crabmeat, or chunks of firm white fish. If using mixed seafood, choose pieces of a similar size so they cook evenly. Avoid adding excessive liquid from frozen seafood, as it can make the casserole watery.
How to Make Creamy Seafood, Spinach and Mushroom Low-Carb Bake
Step 1: Preheat the Oven
Preheat your oven to 375°F (190°C). Lightly grease a medium baking dish with butter or cooking spray.
A dish approximately 9 by 9 inches works well, although a similar-sized casserole dish is also suitable. Choose a dish large enough to hold the seafood and vegetables in a relatively even layer.
Step 2: Cook the Mushrooms
Heat the olive oil and butter in a large skillet over medium heat.
Add the sliced mushrooms and cook for approximately 5–7 minutes, stirring occasionally. The mushrooms should soften and release their moisture. Continue cooking until most of the liquid has evaporated and the mushrooms begin to turn golden.
Add the minced garlic and cook for another 30–60 seconds, stirring frequently to prevent burning.
Cooking the mushrooms before baking is important because it removes excess moisture and gives them a deeper, more concentrated flavor.
Step 3: Add the Spinach
Add the fresh spinach to the skillet in batches if necessary. Stir until the leaves wilt, usually about 2–3 minutes.
If the spinach releases a noticeable amount of liquid, cook it briefly until the excess moisture evaporates. Remove the skillet from the heat and set the vegetables aside.
This step helps keep the finished casserole creamy rather than watery.
Step 4: Prepare the Creamy Sauce
In a medium bowl, combine the softened cream cheese, heavy cream, sour cream, Italian seasoning, onion powder, lemon juice, paprika, salt, and black pepper.
Whisk until the mixture is mostly smooth. Stir in the grated Parmesan cheese and half of the shredded mozzarella.
If the cream cheese is too firm to mix easily, let it sit at room temperature for a few minutes before preparing the sauce. You can also gently warm it to soften it, but avoid overheating the mixture.
Taste the sauce and adjust the seasoning as needed.
Step 5: Combine the Seafood and Vegetables
Pat the shrimp dry with paper towels, especially if they were previously frozen. Excess moisture can thin the sauce.
Place the cooked mushrooms and spinach in a large bowl. Add the raw shrimp and creamy sauce, then gently mix until the ingredients are evenly coated.
Transfer the mixture to the prepared baking dish and spread it into an even layer.
Important: Use raw shrimp for this step so it can finish cooking in the oven. If using already-cooked seafood, add it closer to the end of baking to reduce the risk of overcooking.
Step 6: Add the Cheese Topping
Sprinkle the remaining mozzarella cheese evenly over the top.
For an extra cheesy finish, add a little more Parmesan. The mozzarella melts into a soft, golden layer, while Parmesan contributes a savory flavor.
You can adjust the cheese quantities to your taste, keeping in mind that larger amounts may change the recipe’s calories, fat, and protein content.
Step 7: Bake Until Bubbly
Place the baking dish in the preheated oven and bake for approximately 20–25 minutes, or until the sauce is bubbling and the shrimp are opaque and cooked through.
Cooking time can vary depending on the size of the shrimp, the depth of the dish, and whether the ingredients were cold when assembled.
For food safety, cook shrimp until they reach an internal temperature of 145°F (63°C). Check the thickest pieces with a food thermometer when possible.
If you want a more golden top, briefly place the casserole under the broiler for 1–2 minutes. Watch it closely because cheese can brown quickly.
Step 8: Rest and Serve
Remove the casserole from the oven and let it rest for about 5 minutes. This allows the sauce to settle slightly and makes serving easier.
Garnish with chopped parsley, extra Parmesan, and a squeeze of fresh lemon juice if desired.
Serve warm while the cheese is melted and the creamy sauce coats the seafood and vegetables.
Tips for the Best Seafood Bake
Drain Excess Moisture
Mushrooms, spinach, and thawed seafood can release a surprising amount of water. Cook the vegetables until their moisture has mostly evaporated, and pat thawed seafood dry before using it.
This is one of the most important steps for achieving a thick, creamy casserole.
Avoid Overcooking the Shrimp
Shrimp cook quickly and can become rubbery if left in the oven too long. Smaller shrimp may finish cooking sooner than larger ones, so begin checking the casserole toward the earlier end of the recommended baking time.
Soften the Cream Cheese
Room-temperature cream cheese blends more easily with the cream and sour cream. This helps create a smoother sauce with fewer lumps.
Choose Cheese That Melts Well
Mozzarella provides a stretchy, melted topping, while Parmesan adds a more intense savory flavor. You can also use Monterey Jack or a small amount of sharp cheddar.
Adjust the Seasoning Carefully
Seafood tastes delicious with garlic, lemon, black pepper, and mild herbs. Taste the sauce before adding the seafood, and remember that Parmesan already contributes saltiness.
Easy Variations
Creamy Crab, Spinach and Mushroom Bake
Replace half the shrimp with cooked crabmeat. Fold the crab into the sauce gently to keep the pieces intact. Because the crab is already cooked, add it shortly before baking and heat until the entire casserole is hot.
Salmon and Spinach Low-Carb Bake
Replace the shrimp with bite-sized pieces of boneless salmon. Arrange the pieces throughout the mixture and bake until the salmon is cooked through. Check the thickest piece for an internal temperature of 145°F (63°C).
Spicy Seafood Casserole
Add extra red pepper flakes or a little cayenne pepper to the sauce. For a deeper smoky flavor, increase the paprika slightly.
Extra-Garlicky Version
Add one additional minced garlic clove and finish the casserole with a little fresh parsley. A small squeeze of lemon helps balance the richness.
Dairy-Free Alternative
A dairy-free version requires substitutions for the cream cheese, sour cream, heavy cream, and cheese topping. Choose unsweetened, cooking-appropriate alternatives that work well when heated. The texture and flavor will differ from the original recipe, and the carbohydrate content will depend on the products selected.
What to Serve with This Low-Carb Seafood Bake
This casserole is filling enough to serve on its own, but it also pairs well with simple sides.
- Roasted broccoli: Adds a little crunch and complements the creamy sauce.
- Cauliflower rice: A useful low-carb alternative to traditional rice.
- Zucchini noodles: Provide a light vegetable side that works well with the sauce.
- Fresh green salad: A crisp salad with lemon vinaigrette balances the richness of the cheese.
- Roasted asparagus: Offers a fresh, slightly earthy flavor.
- Garlic green beans: Add color and a satisfying texture without overpowering the seafood.
For a more substantial meal, serve the casserole with a side salad and roasted vegetables.
How to Store Leftovers
Refrigeration
Allow the casserole to cool slightly, then transfer leftovers to an airtight container. Refrigerate within 2 hours of cooking and use within 3–4 days.
For the best texture, store individual portions separately so they are easy to reheat.
Reheating
Reheat individual portions in the microwave in short intervals, stirring or checking between intervals when possible. You can also reheat the casserole in an oven-safe dish at 325°F (165°C) until thoroughly heated.
Avoid reheating seafood repeatedly, as this can make it dry and rubbery. Reheat only the portion you plan to eat.
Can You Freeze It?
Cream-based casseroles can separate or become grainy after freezing and thawing. Seafood texture can also change, so freezing is not the best option for this recipe.
If you do freeze leftovers, place them in a freezer-safe container and thaw them in the refrigerator before reheating. Expect some change in the sauce texture, and make sure the food is reheated thoroughly.
Frequently Asked Questions
1. Is Creamy Seafood, Spinach and Mushroom Bake low-carb?
This recipe is designed to be low in carbohydrates because it does not contain pasta, rice, potatoes, or breadcrumbs. However, the exact carbohydrate count depends on the seafood, vegetables, dairy products, and serving size. Calculate the nutrition using the specific ingredients you use if you are following a strict low-carb or ketogenic plan.
2. Can I use frozen seafood?
Yes. Thaw frozen seafood in the refrigerator or according to the package instructions, then drain and pat it dry before adding it to the casserole. Excess water can make the sauce thin. Do not leave seafood at room temperature for extended periods while thawing.
3. Can I make this casserole ahead of time?
You can prepare the mushroom-spinach mixture and creamy sauce ahead of time and refrigerate them separately. For the best seafood texture, combine the sauce with the raw seafood shortly before baking. If assembling ahead, keep the dish refrigerated and avoid leaving it at room temperature.
4. How do I keep the casserole from becoming watery?
Cook the mushrooms until their liquid evaporates, allow excess moisture to escape from the spinach, and thoroughly drain thawed seafood. Avoid adding frozen seafood directly to the baking dish. These simple steps help the creamy sauce remain thick.
5. Can I use a different type of seafood?
Absolutely. Shrimp, scallops, crabmeat, salmon, and firm white fish can all work. Adjust cooking time according to the type and size of seafood. If using precooked seafood, add it later in the process or reduce the baking time to prevent overcooking.
6. How can I tell when the casserole is ready?
The sauce should be bubbling around the edges, the cheese should be melted, and the seafood should be fully cooked. Shrimp should be opaque throughout and reach 145°F (63°C). If using other seafood, check its doneness and safe cooking temperature as appropriate.
Final Thoughts
Creamy Seafood, Spinach and Mushroom Low-Carb Bake is a comforting, flavorful dish that combines tender seafood, savory mushrooms, fresh spinach, and a rich garlic cream sauce beneath a layer of melted cheese. It is easy enough for a weeknight dinner yet special enough to serve when you want something a little different.
With a few simple preparation steps, you can create a creamy casserole without traditional high-carbohydrate fillers. Customize it with your favorite seafood, adjust the seasonings, and serve it with roasted vegetables or a crisp salad for a satisfying meal.
Make this seafood bake your own, and enjoy a warm, cheesy dinner packed with flavor in every bite.