Hey, friend! Let’s talk about a dish that’s like a warm hug in a casserole dish: Cheesy Spaghetti Squash Gratin. This recipe is a cozy, veggie-packed masterpiece, combining tender spaghetti squash strands with a creamy, cheesy sauce and a golden, bubbly topping. It’s got all the comfort of mac and cheese but with a lighter, low-carb twist that doesn’t skimp on flavor. Think nutty squash, melty cheddar, and a hint of garlic, all baked to perfection. It’s perfect for chilly weeknights, holiday side dishes, or even as a vegetarian main when you want something hearty yet wholesome. I started making this a few years back when I was looking for ways to use up a bumper crop of spaghetti squash from my garden, and now it’s a fall and winter staple in my kitchen. It’s so easy, so cheesy, and so darn good!
Why You’ll Love This Recipe
- Low-Carb Comfort: Swaps pasta for spaghetti squash, making it keto-friendly and lighter but still super satisfying.
- Cheesy Goodness: Loaded with cheddar and Parmesan for that irresistible, melty, golden crust.
- Easy to Make: No fancy skills or tools needed—just roast, mix, and bake.
- Family-Friendly: Even veggie-skeptics love the cheesy, creamy vibes—perfect for kids or picky eaters.
- Versatile: Serve it as a side, a main, or even a make-ahead lunch for the week.
- Budget-Friendly: Uses affordable ingredients like squash, cheese, and pantry staples.
- Customizable: Add protein, swap cheeses, or spice it up to suit your taste.
Ingredients You’ll Need
- Spaghetti Squash: The star of the show—look for a medium-sized one (about 2–3 pounds) for easy handling.
- Cheddar Cheese: Sharp cheddar adds bold flavor; shred it yourself for the best melt.
- Parmesan Cheese: Grated Parm gives a nutty, salty kick to the topping.
- Heavy Cream: Creates that luscious, creamy sauce that ties everything together.
- Butter: For roasting the squash and adding richness to the gratin.
- Garlic: Fresh minced garlic is a must for savory depth.
- Onion: A small one, finely diced, for subtle sweetness and flavor.
- Flour: Just a bit to thicken the sauce—gluten-free flour works too.
- Salt and Pepper: To season the squash and sauce perfectly.
- Nutmeg (optional): A pinch adds warmth and enhances the creamy flavors.
- Breadcrumbs (optional): Panko or regular breadcrumbs for a crunchy topping—skip for keto or gluten-free.
(Note: A complete list of ingredients with exact measurements is included in the instructions section below.)
How to Make It (Step-by-Step Instructions)
Step 1: Roast the Spaghetti Squash
Preheat your oven to 400°F. Carefully slice a medium spaghetti squash in half lengthwise and scoop out the seeds with a spoon. Rub the cut sides with 1 tablespoon of melted butter and sprinkle with a pinch of salt and pepper. Place the halves cut-side down on a parchment-lined baking sheet and roast for 35–45 minutes, until the flesh is tender and easily pierced with a fork. Let it cool slightly, then use a fork to scrape out the strands into a large bowl. Pro tip: Don’t overcook the squash—it should be tender but not mushy to hold its shape in the gratin.
Step 2: Prep the Baking Dish
Lower the oven to 375°F. Grease a 2-quart baking dish (like an 8×8 or 9×9-inch pan) with butter or non-stick spray. This ensures easy serving and a touch of extra flavor. Set the dish aside while you make the sauce.
Step 3: Make the Creamy Cheese Sauce
In a large skillet over medium heat, melt 2 tablespoons of butter. Add 1 small finely diced onion and cook for 4–5 minutes until soft and translucent. Stir in 2 minced garlic cloves and cook for 30 seconds until fragrant—don’t let it burn! Sprinkle 2 tablespoons of flour over the mixture and stir for 1 minute to cook out the raw flour taste. Slowly pour in 1 cup of heavy cream, whisking constantly to avoid lumps. Cook until the sauce thickens slightly, about 2–3 minutes. Remove from heat and stir in 1 cup of shredded sharp cheddar, a pinch of nutmeg (if using), and salt and pepper to taste. The sauce should be smooth and cheesy.
Step 4: Combine Squash and Sauce
Add the roasted spaghetti squash strands to the cheese sauce in the skillet (or a large bowl if your skillet’s too small). Gently toss to coat the squash evenly, being careful not to break the strands too much. Taste and adjust seasoning if needed. If you’re adding extras like cooked bacon or spinach, fold them in now.
Step 5: Assemble the Gratin
Transfer the squash mixture to the greased baking dish, spreading it evenly. Sprinkle ½ cup of grated Parmesan and an additional ½ cup of shredded cheddar over the top. For a crunchy finish, scatter ¼ cup of panko breadcrumbs mixed with 1 tablespoon of melted butter over the cheese (skip this for keto or gluten-free). The cheese and crumbs will create that gorgeous golden crust.
Step 6: Bake to Golden Perfection
Bake uncovered for 20–25 minutes, until the top is bubbly and golden brown. If the top isn’t browning enough, pop it under the broiler for 1–2 minutes, watching closely to avoid burning. Let the gratin rest for 5 minutes before serving—this helps it set and makes scooping easier.
Step 7: Serve and Savor
Scoop the gratin onto plates or into bowls and serve hot. Garnish with a sprinkle of fresh parsley or chives for a pop of color if you’re feeling fancy. Pair it with a crisp salad or roasted veggies for a complete meal, or serve as a side to grilled chicken or steak.
Helpful Tips
- Meal Prep Made Easy: Roast the squash and make the sauce up to 2 days ahead, then assemble and bake when ready. You can also bake the entire gratin, cool, and refrigerate for up to 3 days—reheat at 350°F for 15–20 minutes.
- Storing Leftovers: Store in an airtight container in the fridge for up to 4 days. The flavors get even better as it sits!
- Reheating Without Drying Out: Reheat in the microwave with a splash of cream or milk, or cover with foil and warm in a 325°F oven for 10–15 minutes to keep it creamy.
- Perfect Pairings: Serve with a green salad with vinaigrette, roasted Brussels sprouts, or garlic bread for a cozy meal. A glass of crisp white wine like Sauvignon Blanc or a light red like Pinot Noir complements the cheesy, nutty flavors.
- Creative Twists: Add cooked bacon, sausage, or shredded chicken for extra protein. Toss in sautéed mushrooms, spinach, or kale for more veggies. Swap cheddar for Gruyère or mozzarella for a different flavor profile. For a spicy kick, add a pinch of cayenne or red pepper flakes to the sauce.
- Avoid Watery Gratin: After roasting, let the squash sit for a few minutes and gently press out any excess moisture with a clean kitchen towel. This keeps the gratin creamy, not soggy.
Frequently Asked Questions (FAQs)
Can I make this ahead of time?
Yes! You can roast the squash and prep the sauce up to 2 days in advance, storing them separately in the fridge. Assemble and bake when ready, or bake the whole dish and reheat before serving.
Can I freeze this recipe?
You can freeze the baked gratin for up to 2 months. Cool completely, wrap tightly in plastic wrap and foil, and freeze. Thaw in the fridge overnight and reheat at 350°F, covered, until warmed through. Add extra cheese on top before reheating for a fresh look.
What if I don’t have spaghetti squash?
You can use zucchini noodles or even cooked pasta (though it won’t be low-carb). Drain zucchini well to avoid excess moisture. For pasta, reduce the cream slightly to prevent a runny sauce.
Is this recipe good for meal prep?
Absolutely! Portion it into containers after baking for easy lunches or dinners. It reheats well and stays creamy, making it a great make-ahead option.
How do I make it vegetarian?
This recipe is naturally vegetarian! Just ensure your cheeses are vegetarian (some Parmesans use animal rennet) and skip any meat add-ins. For vegan, use plant-based cream, cheese, and butter substitutes, but the texture may vary.
I make this Cheesy Spaghetti Squash Gratin all the time, especially in the fall when squash is everywhere—it’s my go-to for cozy dinners or impressing guests without much effort. For a fun serving idea, try scooping it into individual ramekins before baking for a cute, personal-sized portion. Give it a whirl and let me know how it turns out—I’d love to hear if it becomes a favorite in your kitchen too!
Cheesy Spaghetti Squash Gratin
Ingredients
- 1 medium spaghetti squash
- 2 tablespoons butter
- 1 small onion finely chopped
- 2 cloves garlic minced
- ½ cup sour cream
- 1 cup shredded cheddar cheese divided
- ¼ teaspoon salt
- ¼ teaspoon black pepper
- ¼ teaspoon paprika
- 2 tablespoons grated Parmesan cheese
Instructions
- Preheat the oven: Set your oven to 375°F (190°C). Grease a baking dish with butter or cooking spray.
- Prepare the squash: Cut the spaghetti squash in half lengthwise and scoop out the seeds. Place the halves cut side down on a baking sheet lined with parchment paper. Roast for 30–40 minutes, or until the squash is tender and easily pierced with a fork.
- Shred the squash: Once roasted, use a fork to scrape the flesh of the squash into spaghetti-like strands. Set aside.
- Sauté aromatics: In a large skillet, melt butter over medium heat. Add the chopped onion and minced garlic, cooking for 2–3 minutes until softened and fragrant.
- Combine ingredients: Stir in the sour cream, ½ cup of cheddar cheese, salt, pepper, and paprika. Cook for another 2–3 minutes until the cheese is melted and the mixture is smooth.
- Mix squash and sauce: Add the cooked spaghetti squash strands to the skillet, mixing well to combine.
- Transfer to baking dish: Transfer the mixture to the prepared baking dish.
- Add toppings: Sprinkle the remaining ½ cup of shredded cheddar cheese and grated Parmesan over the top.
- Bake: Bake for 15–20 minutes, or until the top is golden and bubbly.
- Serve: Serve warm and enjoy the creamy, cheesy goodness of this spaghetti squash gratin!
Notes
- For added flavor, consider mixing in cooked bacon bits or sautéed mushrooms.
- Ensure the squash is fully cooked and tender before scraping to achieve the best texture.
- This dish pairs well with grilled chicken or a fresh green salad.
