This Parmesan Butternut Squash Gratin transforms simple autumn squash into a golden, crispy, and flavorful side dish.
Packed with fiber and plant-based nutrients, it’s a nourishing choice that pairs creamy, savory parmesan with crunchy panko.
Quick to assemble and oven-ready, it’s a low-saturated-fat, high-fiber recipe perfect for everyday dinners, cozy family meals, or effortless holiday sides.
Parmesan Butternut Squash Gratin
Equipment
- 13 x 9-inch baking dish
- small saucepan
- Mixing bowl
- Measuring Cups and Spoons
- Knife and cutting board
- Cooking spray or oil
- Spoon or spatula
Ingredients
- 1 2 1/2 lb butternut squash, peeled, halved, seeded, and sliced 1/2-inch thick
- 5 Tbsp 70 g salted butter
- 3 cloves garlic minced
- Salt to taste
- Freshly ground black pepper to taste
- ½ cup 35 g plain panko bread crumbs
- ½ cup 42 g finely grated parmesan cheese
- ½ tsp dried thyme
- ¼ tsp dried sage
- ¼ cup chopped fresh parsley
Instructions
- Preheat and Prepare Baking Dish: Begin by preheating your oven to 375°F (190°C). While the oven warms, take a 13 x 9-inch baking dish and lightly coat it with cooking spray or a thin layer of butter. This ensures the squash won’t stick during baking and makes cleanup easier. Arrange your sliced butternut squash in the dish in slightly overlapping rows, creating a neat and uniform layer.
- Melt Butter and Infuse Garlic: Place 5 tablespoons (70 g) of salted butter in a small saucepan over medium heat. Allow the butter to melt completely, then reduce the heat to low. Add the minced garlic and cook gently for about 1 minute, stirring constantly. This step infuses the butter with a rich, aromatic garlic flavor without burning the garlic, which could turn bitter. Once fragrant, remove the saucepan from heat to prevent overcooking.
- Prepare Crunchy Topping Mixture: In a medium mixing bowl, combine 1/2 cup (35 g) of plain panko bread crumbs, 1/2 cup (42 g) finely grated parmesan cheese, 1/2 teaspoon dried thyme, and 1/4 teaspoon dried sage. Lightly season with a pinch of salt and freshly ground black pepper, keeping in mind the parmesan already adds some saltiness. Drizzle 2 tablespoons of the warm garlic butter over this mixture, then toss thoroughly until the crumbs are evenly coated and slightly moistened. This step ensures the topping will bake to a golden, crispy perfection.
- Brush Squash with Garlic Butter: Using a pastry brush or spoon, evenly brush the remaining garlic butter over the arranged squash slices in the baking dish. Lightly sprinkle with additional salt and pepper to season each slice. This step not only adds flavor but also helps the squash slices roast evenly and stay moist while baking.
- Apply Topping and Layer Evenly: Sprinkle the prepared panko and parmesan topping evenly over the buttered squash slices. Make sure the topping covers the squash uniformly without clumping, which helps achieve a consistent golden-brown crust during baking. Press lightly with your fingers or the back of a spoon to ensure the crumbs adhere to the buttered squash surface.
- Bake the Squash Gratin: Place the baking dish in the preheated oven and bake for 35 to 40 minutes. Check the squash for tenderness by inserting a fork; it should pierce easily without being mushy. The topping should be lightly golden at this stage. If the topping isn’t deeply browned, increase the oven temperature to 425°F (220°C) and bake for an additional 5 minutes, keeping a close eye to prevent burning.
- Garnish and Serve Warm: Once the squash is tender and the topping has a beautiful golden crust, remove the dish from the oven. Sprinkle 1/4 cup of freshly chopped parsley over the top for a pop of color and a fresh, herbaceous note. Serve immediately while warm, either as a comforting weekday side or an impressive addition to holiday meals.
Notes
- Choose a medium-sized butternut squash for even cooking and manageable slices.
- Slice the squash evenly, about 1/2 inch thick, to ensure uniform tenderness and consistent baking.
- Fresh garlic works best, but roasted garlic can add a sweeter, milder flavor.
- Use freshly grated parmesan for superior flavor and better melting compared to pre-grated varieties.
- Panko breadcrumbs create a crisp topping—avoid regular breadcrumbs if you want a crunchier gratin.
- Lightly overlapping the squash slices helps the flavors meld while preventing uneven cooking.
- Keep an eye on the topping during the final baking stage to avoid burning.
Chef’s Secrets For Perfect Gratin
The secret to a flawless squash gratin lies in layering flavor and texture.
First, don’t rush the garlic-butter step; gently cooking it over low heat maximizes aroma without bitterness.
Next, combine the panko, parmesan, and herbs thoroughly so each breadcrumb carries flavor, ensuring a crisp, golden crust.
For extra richness, some chefs like to dot the squash slices with small butter cubes before topping.
Lastly, slightly overlapping the slices allows each bite to be tender yet structured, creating a visually appealing dish.
Serving Suggestions For Cozy Meals
This gratin pairs beautifully with roasted or grilled proteins such as chicken, pork, or salmon, making it perfect for weeknight dinners or holiday spreads.
For a vegetarian meal, serve alongside quinoa, lentils, or a fresh leafy salad.
Garnish with a sprinkle of fresh parsley or a few toasted nuts for added texture.
Its warm, cheesy crunch also makes it a satisfying side for autumn-themed meals or festive gatherings.
Storage Tips To Keep Fresh
Store any leftovers in an airtight container in the refrigerator for up to 3–4 days.
To reheat, cover with foil and warm in a 350°F (175°C) oven for 10–15 minutes until heated through, preserving the crisp topping.
Avoid microwaving directly, as it can make the topping soggy.
For longer storage, the gratin can be frozen for up to 2 months; thaw overnight in the refrigerator and reheat as above.
Frequently Asked Questions
1. Can I make this gratin ahead of time?
Absolutely! You can assemble the squash and topping a day in advance, cover it, and refrigerate. Bake just before serving for the best texture and flavor.
2. Can I use frozen butternut squash instead of fresh?
Yes, but drain well and pat dry to avoid excess moisture, which can make the gratin watery. Adjust baking time slightly as frozen squash may cook faster.
3. Can I make this dish dairy-free?
You can substitute the butter with plant-based margarine or olive oil and use a vegan parmesan alternative. Keep in mind the flavor and browning may be slightly different.
4. How can I make the topping extra crispy?
Toast the panko lightly in a dry pan before mixing with butter and parmesan. This enhances crunch and adds a nutty flavor to the topping.
5. Can I add other vegetables to the gratin?
Yes! Thin slices of sweet potato, zucchini, or carrots can be layered with the squash. Just make sure all vegetables are cut to similar thickness for even baking.
