If you’re craving something creamy, savory, and effortless for dinner, this Keto Garlic Parmesan Shrimp Casserole fits the bill. It’s rich without being heavy, full of zesty garlic, and layered with tender shrimp and melty cheese. Best of all, it comes together quickly with simple ingredients you probably already have.
This is the kind of dish that makes weeknights feel special without a ton of work. Serve it with a crisp side salad or roasted veggies, and you’re set.
Keto Garlic Parmesan Shrimp Casserole - Creamy, Comforting, and Low-Carb
Ingredients
- 1.5 pounds raw shrimp, peeled and deveined (medium or large)
- 2 tablespoons olive oil or avocado oil
- 4 tablespoons unsalted butter
- 5–6 cloves garlic, minced
- 1 cup heavy cream
- 3 ounces cream cheese, softened and cubed
- 1 cup grated Parmesan cheese, divided (about 3/4 cup for sauce, 1/4 cup for topping)
- 1/2 cup shredded mozzarella (for extra melt on top)
- 3 cups fresh spinach (or 1.5 cups frozen, thawed and well-drained)
- 3 cups riced cauliflower (fresh or frozen, thawed)
- 1 teaspoon Italian seasoning
- 1/2 teaspoon crushed red pepper flakes (optional)
- Zest of 1/2 lemon and 1 tablespoon lemon juice
- Salt and black pepper, to taste
- Fresh parsley, chopped, for garnish
Instructions
- Preheat the oven to 375°F (190°C). Lightly grease a 9x13-inch baking dish or similar casserole pan.
- Pat the shrimp dry with paper towels. Season with salt, pepper, and half the Italian seasoning. Set aside while you start the sauce.
- Heat a large skillet over medium heat. Add the olive oil and 2 tablespoons butter. When the butter melts, add the garlic and cook for 30–45 seconds until fragrant, not browned.
- Stir in the heavy cream and cream cheese. Whisk until the cream cheese fully melts and the mixture is smooth. Simmer gently for 2–3 minutes to slightly thicken.
- Add 3/4 cup Parmesan, the remaining Italian seasoning, and the red pepper flakes if using. Stir until melted and creamy. Season with salt and pepper to taste.
- Add the spinach to the sauce and cook until wilted, 1–2 minutes. Stir in the lemon zest and lemon juice. Taste and adjust seasoning. The sauce should be rich, garlicky, and bright.
- In a separate skillet, melt the remaining 2 tablespoons butter over medium-high heat. Add the cauliflower rice, season with a little salt and pepper, and cook for 3–4 minutes to steam off excess moisture. This helps the casserole stay creamy, not watery.
- Spread the cauliflower rice evenly in the prepared baking dish as a base layer.
- Arrange the seasoned shrimp over the cauliflower rice. Pour the garlic Parmesan sauce with spinach evenly over the top, making sure the shrimp are coated.
- Sprinkle with the remaining Parmesan and the mozzarella. This gives you that bubbly, golden top.
- Bake for 12–15 minutes, until the shrimp are opaque and just cooked through. If you want extra browning, broil for 1–2 minutes at the end, watching closely.
- Let the casserole rest for 5 minutes. Garnish with fresh parsley and serve hot.
What Makes This Special
This casserole brings the best of both worlds: comfort food satisfaction and keto-friendly macros. The sauce is creamy without using flour or starch, relying instead on cream, cheese, and a quick simmer to thicken naturally.
Shrimp cooks fast, so you’ll have dinner on the table in under 40 minutes, start to finish. It also reheats well, so lunch the next day is already handled. You’ll taste bold garlic, nutty Parmesan, and a hint of lemon that brightens everything.
The addition of spinach and cauliflower rice adds texture and fiber, keeping it low-carb while still feeling complete. It’s versatile, too—swap in different cheeses or veggies and make it your own.
What You’ll Need
- 1.5 pounds raw shrimp, peeled and deveined (medium or large)
- 2 tablespoons olive oil or avocado oil
- 4 tablespoons unsalted butter
- 5–6 cloves garlic, minced
- 1 cup heavy cream
- 3 ounces cream cheese, softened and cubed
- 1 cup grated Parmesan cheese, divided (about 3/4 cup for sauce, 1/4 cup for topping)
- 1/2 cup shredded mozzarella (for extra melt on top)
- 3 cups fresh spinach (or 1.5 cups frozen, thawed and well-drained)
- 3 cups riced cauliflower (fresh or frozen, thawed)
- 1 teaspoon Italian seasoning
- 1/2 teaspoon crushed red pepper flakes (optional)
- Zest of 1/2 lemon and 1 tablespoon lemon juice
- Salt and black pepper, to taste
- Fresh parsley, chopped, for garnish
Step-by-Step Instructions
- Preheat the oven to 375°F (190°C). Lightly grease a 9×13-inch baking dish or similar casserole pan.
- Pat the shrimp dry with paper towels.
Season with salt, pepper, and half the Italian seasoning. Set aside while you start the sauce.
- Heat a large skillet over medium heat. Add the olive oil and 2 tablespoons butter.
When the butter melts, add the garlic and cook for 30–45 seconds until fragrant, not browned.
- Stir in the heavy cream and cream cheese. Whisk until the cream cheese fully melts and the mixture is smooth. Simmer gently for 2–3 minutes to slightly thicken.
- Add 3/4 cup Parmesan, the remaining Italian seasoning, and the red pepper flakes if using.
Stir until melted and creamy. Season with salt and pepper to taste.
- Add the spinach to the sauce and cook until wilted, 1–2 minutes. Stir in the lemon zest and lemon juice.
Taste and adjust seasoning. The sauce should be rich, garlicky, and bright.
- In a separate skillet, melt the remaining 2 tablespoons butter over medium-high heat. Add the cauliflower rice, season with a little salt and pepper, and cook for 3–4 minutes to steam off excess moisture.
This helps the casserole stay creamy, not watery.
- Spread the cauliflower rice evenly in the prepared baking dish as a base layer.
- Arrange the seasoned shrimp over the cauliflower rice. Pour the garlic Parmesan sauce with spinach evenly over the top, making sure the shrimp are coated.
- Sprinkle with the remaining Parmesan and the mozzarella. This gives you that bubbly, golden top.
- Bake for 12–15 minutes, until the shrimp are opaque and just cooked through.
If you want extra browning, broil for 1–2 minutes at the end, watching closely.
- Let the casserole rest for 5 minutes. Garnish with fresh parsley and serve hot.
Keeping It Fresh
– Store leftovers in an airtight container in the fridge for up to 3 days. – Reheat gently at 325°F (165°C) or in a covered skillet over low heat to keep the sauce silky. – Avoid microwaving on high; it can make shrimp rubbery. Short bursts on medium power work better. – This casserole can be frozen, but dairy sauces may separate.
If you freeze it, wrap tightly and thaw in the fridge before reheating. Stir a splash of cream into the sauce after reheating to restore creaminess.
Health Benefits
– High in protein: Shrimp provides lean protein that supports muscle maintenance and keeps you full. – Low-carb and keto-friendly: Cauliflower rice and leafy spinach add volume and fiber without spiking carbs. – Rich in micronutrients: Shrimp contains selenium and iodine; spinach adds vitamin K and folate. – Satiating fats: The combination of cream, butter, and cheese supports ketosis and steady energy.
Pitfalls to Watch Out For
– Overcooking shrimp: Shrimp cook fast. Bake just until opaque.
Overcooked shrimp turn tough. – Watery casserole: Sauté the cauliflower rice first and squeeze excess water from frozen spinach if using. This keeps the sauce velvety. – Too salty: Parmesan is salty. Season in stages and taste the sauce before adding more salt. – Broken sauce: Boiling can cause dairy to separate.
Keep the sauce at a gentle simmer and add cheese gradually.
Alternatives
– Protein swaps: Try chicken breast (thinly sliced and pre-cooked), scallops, or a mix of shrimp and crab. – Dairy-free twist: Use coconut cream and a dairy-free Parmesan-style cheese. Flavor with nutritional yeast for depth. – Veggie variations: Sub spinach with kale, Swiss chard, or sautéed zucchini. Broccoli florets also work well. – Cheese changes: Romano or Asiago add a sharper bite.
Provolone or Gruyère give a luxe melt. – Herb boosts: Fresh basil or thyme can replace Italian seasoning. A pinch of smoked paprika adds warmth. – Spice it up: Add more red pepper flakes or a dash of hot sauce to the sauce for gentle heat.
FAQ
Can I use frozen shrimp?
Yes. Thaw completely in the fridge, then pat very dry.
Excess moisture will thin the sauce and steam the shrimp.
Do I have to use cauliflower rice?
No, but it helps make the dish filling and keeps it low-carb. You can skip it and serve the shrimp and sauce over zoodles or roasted asparagus.
How can I thicken the sauce without flour?
Simmer the cream gently to reduce, melt in cream cheese and Parmesan, and avoid high heat. It naturally thickens into a silky sauce.
What size shrimp should I buy?
Medium to large shrimp (about 21–30 per pound) are ideal.
They cook evenly and don’t get lost in the casserole.
Can I make it ahead?
Partially. Cook the sauce and cauliflower rice, then assemble without baking and refrigerate up to 24 hours. Add shrimp just before baking for best texture.
Is this spicy?
Only if you add red pepper flakes.
Keep it mild by skipping them, or add more for a kick.
How many carbs per serving?
Exact counts vary with brands, but this casserole typically lands around 5–7 net carbs per serving. Check your ingredient labels for precision.
What can I serve with it?
A simple arugula salad with lemon vinaigrette, roasted Brussels sprouts, or sautéed green beans all pair nicely.
Can I use pre-cooked shrimp?
You can, but add them at the very end of baking and heat just until warm to avoid rubbery texture.
How do I prevent a fishy taste?
Use fresh shrimp or high-quality frozen shrimp, fully thawed and dried. The lemon zest and juice also keep flavors clean and bright.
Wrapping Up
This Keto Garlic Parmesan Shrimp Casserole is simple, satisfying, and flexible.
It’s built on real, flavorful ingredients and comes together without fuss. Keep the technique light and gentle, season as you go, and you’ll end up with a creamy, garlicky bake that’s perfect for busy nights and special dinners alike. Enjoy it fresh, tweak it to your taste, and make it a new go-to in your low-carb rotation.