Easy Butternut Squash Gratin Leeks (Print View)
Layers of butternut squash paired with sautéed leeks, sage, and gruyere cheese. Finished with walnuts, this dish is perfect for gatherings or festive occasions.
# What You'll Need:
→ Main components
01 -
Two pounds of butternut squash, peeled and cut into very thin slices (1/8 inch)
02 -
2 medium leeks, sliced thinly
03 -
4 garlic cloves, roughly chopped
04 -
15 sage leaves, minced (set aside 8 extra leaves if you want a crispy topping)
05 -
2 tablespoons of butter or olive oil
→ For the cream sauce
06 -
1/2 teaspoon each of salt and black pepper
07 -
1/2 teaspoon onion powder (use this only if you want an extra flavor boost)
08 -
1/2 teaspoon nutmeg
09 -
1 cup of heavy cream or coconut milk (perfect if you're avoiding dairy)
→ Layers and toppings
10 -
1/4 cup of water
11 -
3 ounces of gruyere cheese (substitute with parmesan or a vegan cheese option)
12 -
1/2 cup of chopped walnuts
# Directions:
01 -
Set your oven to 375°F (190°C) so it heats up while you prep.
02 -
Carefully peel and slice the butternut squash into thin, 1/8-inch rounds. Set aside the prettiest 12-15 slices — they'll be for the top later. Scoop out any seeds once you hit them, then keep slicing the rest. It may help to sort the slices into three piles for layering.
03 -
Wash the leek slices (this gets rid of dirt and also helps them cook better). Heat up oil or butter in a large pan on medium heat. Toss in the leeks and cook them for around 8 to 10 minutes, covering them partially so they soften quicker. Add garlic, sage, and a sprinkle of salt, then let it all cook for another 2 or 3 minutes. Take it off the heat when they're done.
04 -
In a mixing bowl, combine the cream or coconut milk, nutmeg, salt, black pepper, and onion powder (if using). Whisk it all until blended.
05 -
Grab a baking dish about 9x13 inches or a round one that’s 11-12 inches wide. Spread 1/4 cup water across the base. Start layering: place the squash slices slightly overlapping, scatter on half the leeks, drizzle with 1/3 cup of the cream mixture, and sprinkle 1/3 of the cheese. Repeat these steps for another layer (use uneven squash slices here since they’ll be hidden). Finish it off with the best-looking squash, the remaining cream mixture, the rest of the cheese, and the walnuts on top. Lightly press everything down to even it out.
06 -
Cover the dish with foil lined with parchment paper to keep it from sticking. Bake at 375°F for 45 minutes. Take off the cover, check if the squash is soft, then raise the oven temperature to 400°F. Bake for another 15 minutes or until the top is golden and bubbly.
# Notes:
01 -
You can put this dish together in advance and keep it in the fridge before baking. Or bake it entirely and warm it up at 350°F later.
02 -
It's best to let the dish come to room temp before baking for even cooking.
03 -
A shallow baking dish tends to give the best results for even cooking.