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This Butternut Squash Au Gratin is such a comforting dish that works perfectly for the holidays or a special occasion. Layered with sautéed leeks, fresh sage, and parmesan cheese for a huge burst of flavor! Bubbly, cheesy, and so comforting. 

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The Best Holiday side dish

I would like to introduce you to a recipe I’ve been making for years. The one dish that gets the most rave reviews and people to ask me for the recipe!

Last year for Friendsgiving, this dish was the first one to be gobbled up. Each year for Thanksgiving, this is the dish my family looks forward to the most. And a few of them aren’t huge fans of butternut squash! But this variation, it’s special.

Butternut Squash Au Gratin is loaded with sautéed leeks and fresh sage, perfectly tender nutty squash, parmesan cheese, and a little heavy cream to give us the decadence we crave. Yup, I am sure you are going to love it as much as everyone else.

Over the years, I’ve also enjoyed experimenting with other holiday flavors. Like the sweet and savory Maple Balsamic Brussels Sprouts with Cranberries and Bacon or the comforting richness of Sweet Potato and Apple Casserole. Both bring their own festive flair to the table and keep the holiday spread exciting.

It’s finally time for my Butternut Squash Au Gratin to make it to the blog!

How to make Butternut Squash Au Gratin:

Let’s gather up our ingredients:

  • butternut squash bulbs (you can cheat here and get the pre-cut, but it requires ALOT)
  • butter
  • leeks
  • garlic
  • fresh sage leaves
  • heavy cream
  • parmesan cheese
  • salt and pepper to taste

It does require a little bit of prep time, but the good news is, you can also make ahead.

Directions:

  1. Peel and cut your butternut squash into cubes. Drizzle with a bit of oil and salt. Roast in the oven at 400 degrees for 20-25 minutes.
  2. While the butternut squash is roasting, saute the leeks, sage and garlic with butter on the stovetop. You want this mixture to lightly golden and softened.
  3. We put it altogether by doing two layers of squash and the leek/sage mixture. Top with cream, then the parmesan cheese.
  4. Transfer to the oven to bake. You’ll bake for about 30 minutes, or until the mixture is nice and bubbly.

Can you make ahead?

YES!! You can make one day ahead; this is a great option if serving this for Thanksgiving. Follow the directions above, but stop at the cream and parmesan addition. Cover with foil and refrigerate. When ready to bake, bring to room temperature and pour in the cream. Top with parmesan and transfer to the oven.

Can I make this Paleo or Dairy-Free?

The answer is YES!!! I have made the dairy-free version before and it turned out yummy. I do prefer the cheesy, bubbly version– in case you were wondering. To make it dairy free, follow these steps:

  1. Roast the butternut squash as mentioned above.
  2. Use avocado oil or ghee to saute the leeks, garlic, and sage.
  3. Create a “cheese” sauce: soak 1/2 cup of cashews in hot water for at least 15 minutes. Drain the water. Place the cashews in a high powered blender with 1 cup chicken broth, 1 tbsp lemon juice, 1 tbsp dijon mustard, 1/2 tsp sea salt, and 1/4 cup nutritional yeast. Blend until completely smooth.
  4. Layer the casserole like mentioned above. Pour the cashew sauce on top. For additional flavor, top with toasted hazelnuts. Bake for 20 minutes.

This cozy bisque is a perfect way to bring warmth and flavor to your Thanksgiving table. As you cook the big meal, let my free Thanksgiving Planning Guide help you keep everything on track so you can savor the holiday, not just serve it.

5 from 1 vote

Butternut Squash Au Gratin

Prep: 35 minutes
Cook: 25 minutes
Servings: 8
Butternut Squash Au Gratin is a decadent side dish that is so perfect for a holiday meal or special occasion! Bubbly parmesan cheese, fresh sage, and sauteed leeks ties this dish together so well.
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Ingredients 

  • 2 large butternut squash
  • 1 tbsp avocado oil or olive oil
  • pinch sea salt
  • 2 tbsp butter
  • 2 cups sliced leeks
  • 3 large cloves garlic, (minced)
  • 2 tbsp fresh chopped sage
  • 3/4 cup heavy cream or half and half
  • 3/4 cup shredded parmesan cheese
  • salt and pepper to taste

Instructions 

  • Preheat the oven to 400 degrees F. Prepare the butternut squash by peeling, removing the seeds, and dicing into cubes. Lightly toss with oil, sprinkle with salt, and assemble across a large sheet pan. Transfer to the oven and roast for about 25 – 30 minutes, or until softened.
  • Meanwhile, heat a large saute pan to medium heat. Add the butter, sliced leeks, garlic, and sage. Saute until softened and golden brown, stirring occasionally. This should take 10-12 minutes. Set aside.
  • Once the butternut squash is ready, remove from oven. Prepare a smaller casserole dish (9×9, 8×11). Layer the dish as follows: start with half of the leek mixture, then arrange half of the butternut squash on top. Add another layer of leeks, and top with another layer of butternut squash. Pour the cream on top, then sprinkle with parmesan cheese.
  • Bake uncovered at 375 F for 27-30 minutes, or until bubbly and golden. Remove from heat. Sprinkle with salt and pepper to taste.

Nutrition

Calories: 190kcal, Carbohydrates: 27g, Protein: 7g, Fat: 8g, Saturated Fat: 4g, Cholesterol: 17mg, Sodium: 169mg, Potassium: 757mg, Fiber: 4g, Sugar: 5g, Vitamin A: 20470IU, Vitamin C: 43mg, Calcium: 247mg, Iron: 2mg

Nutrition information is automatically calculated, so should only be used as an approximation.

Tried this recipe?Mention @wholesomelicious or tag #wholesomelicious!

About Amy Rains

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