Butternut Squash Casserole (Vegetarian)
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This Butternut Squash Casserole (Vegetarian) combines roasted butternut squash, wild rice, mushrooms, leeks, onion, savory herbs, and melted Gruyere cheese. The roasted squash adds a lightly caramelized sweetness to the hearty wild rice and savory vegetables, while Gruyere melts over the top for a rich finish. Serve this vegetarian casserole as a side dish or a meatless main dish for a fall or holiday meal.
Try my Creamy Butternut Squash Orzo next!
Quick Look: Butternut Squash Casserole (Vegetarian)
- Prep Time: 30 minutes
- Cook Time: 45 minutes
- Total Time: 1 hour 15 minutes
- Servings: 8
- Dietary Info: Vegetarian; can be adapted to vegan
- Method: Oven roasting + stovetop cooking + baking
- Technique: Roast the cubed butternut squash, cook the wild rice, sauté the leeks, onion, garlic, and mushrooms with thyme, sage, and cayenne, then combine everything in a casserole dish, top with Gruyere, and bake.
- Flavor/Texture: Savory, earthy, sweet, tender, chewy, cheesy
A Hearty Fall Casserole
This is one of my favorite casseroles because the roasted squash and wild rice make it hearty enough to stand on its own while the leeks, mushrooms, garlic, thyme, and sage add layers of savory flavor.
Roasting the squash first gives it tender pieces with lightly caramelized edges, while the wild rice adds a chewy texture throughout the casserole. The melted Gruyere on top brings everything together into a comforting dish I love serving during the fall and holiday season whenever I want comfort food without the heaviness.
Serve with other fall sides such as 5-Ingredient Jiffy Corn Casserole and Creamy Brussels Sprouts.
Made With Amore,
Table of Contents
Simple Ingredients
This casserole brings together seasonal ingredients for a savory and sweet casserole.
- Butternut Squash: Roasted until tender and slightly caramelized before being added to the casserole.
- Wild Rice: Adds a chewy texture and hearty base to the vegetarian casserole.
- Leeks, Onion, and Garlic: Build the savory vegetable base of the casserole.
- Mushrooms: Add an earthy flavor and hearty texture to the vegetable mixture.
- Gruyere Cheese: Melts over the top of the casserole for a cheesy finish.
See recipe card for full information on ingredients and quantities.
Substitutions & Variations
- Vegan: Use vegan butter in place of butter and a vegan cheese alternative in place of Gruyere.
- Rice: The recipe allows brown rice, quinoa, farro, or white rice in place of wild rice. Try my Stuffed Acorn Squash next!
- Broth: Use vegetable broth, Chicken Broth, or water to cook the rice.
- Dried Fruit: Add dried cherries, craisins, or raisins if desired.
How to Make Butternut Squash Casserole
This butternut squash casserole comes together in layers, with roasted squash, cooked wild rice, sautéed vegetables, and melted Gruyere baked together until hot and bubbly. Follow the step-by-step photos and see the recipe card at the bottom for a printable version.
- Combine the rinsed rice and broth (or water) in a medium saucepan. Cook rice according to package directions on the stove top or rice cooker. Once cooked, fluff the rice with a fork and set aside.
- Toss the cubed butternut squash with olive oil, salt, and pepper. Spread the chopped butternut squash cubes in a single layer on a baking sheet. Roast in the preheated oven for about 25-30 minutes or until the squash is tender and slightly caramelized. Set aside.
- Melt the butter in a large skillet over medium heat. Add the chopped leeks and onion.
- Sauté for about 5-6 minutes until they become translucent and soft. Add the minced garlic and sliced mushrooms to the skillet.
- Cook for an additional 5-6 minutes or until the mushrooms are tender and any liquid they release evaporates. Stir in the dried thyme, sage, cayenne, salt, and pepper.
- Remove from heat, and add the dried fruit (if using).
- In a mixing bowl, combine the cooked wild rice, roasted butternut squash mixture, and the sautéed leek and mushroom mixture.
- Mix well to distribute the ingredients in an even layer. Transfer the mixture to a greased casserole dish.
- Sprinkle the shredded Gruyere cheese over the top of the casserole. Cover the casserole dish with aluminum foil. Bake the casserole in the preheated oven at 350°F (175°C) for about about 15 minutes or until the cheese is melted and bubbly.
- Remove the casserole from the oven and let it cool slightly before serving. Serve the butternut squash casserole warm as a comforting and flavorful vegetarian dish!
Butternut Squash Casserole FAQs
This casserole can be served as a vegetarian main dish as well as a side dish. The wild rice and roasted butternut squash give it a hearty base, while the mushrooms and other vegetables add texture and savory flavor.
Certainly, additional vegetables like spinach, kale, or Roasted Red Peppers can be incorporated for extra flavor and nutrients.
Yes, you can use frozen butternut squash if fresh is unavailable. Thaw and drain the frozen cubes before roasting to prevent excess moisture. You might need to use more than the recommended amount.
You can prepare the components beforehand to save time on busy days or during the holiday season. Roast the butternut squash and cook the wild rice a day in advance. When you’re ready to assemble, the casserole will come together quickly. For storing leftover, cover the casserole dish tightly with plastic wrap or aluminum foil to prevent moisture loss and freezer odors. Refrigerate for up to 3-4 days or freeze for up to 2-3 months.
Serving Suggestions
Serve butternut squash casserole as a vegetarian main dish or alongside a larger meal. For a vegetarian meal, add a Fennel and Orange Salad (Italian Style) and a loaf of fresh Italian Bread Recipe (No Knead Crusty Bread). For a holiday table, pair it with other festive sides such as Hasselback Sweet Potatoes and Vegetable Au Gratin, and a main like Roasted Chicken.
My Pro Tips
Recipe Tips
- Cut the butternut squash into uniform cubes so the pieces roast evenly.
- Spread the squash in a single layer on the baking sheet so it can roast evenly and develop lightly caramelized edges.
- Rinse the wild rice before cooking as directed in the recipe.
- Cook the mushrooms until their liquid evaporates before combining them with the other casserole ingredients.
- Let the casserole cool slightly before serving so it is easier to portion and serve.
More Recipes with Butternut Squash
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Vegetarian Butternut Squash Casserole Recipe
Equipment
Ingredients
For the Roasted Butternut Squash:
- 1 medium butternut squash, peeled, seeded, and cubed
- 2 tablespoons olive oil
- Salt and black pepper to taste
For the Casserole:
- 1 ½ cups wild rice, rinsed (or brown rice, quinoa, farro, or white rice)
- 3 cups vegetable broth, chicken broth, or water
- 2 tablespoons butter, or vegan butter for a vegan version
- 2 leeks, cleaned and chopped
- 1 onion, chopped
- 2 cloves garlic, minced
- 8 ounces mushrooms, sliced
- 1 teaspoon dried thyme
- 1 teaspoon dried sage
- ½ teaspoon cayenne pepper, more if desired
- Salt and pepper to taste
- 1 cup shredded Gruyere cheese, or a vegetarian alternative
- Optional: 1/2 cup dried cherries, craisins, or raisins.
Instructions
- Preheat your oven to 400°F.
- Roast the Butternut Squash: Toss the cubed butternut squash with olive oil, salt, and pepper. Spread the chopped butternut squash cubes in a single layer on a baking pan. Roast in the preheated oven for about 25-30 minutes or until the squash is tender and slightly caramelized. Set aside.
- Cook the Rice: Combine the rinsed rice and broth (or water) in a medium saucepan. Cook rice according to package directions on the stove top or rice cooker. Once cooked, fluff the rice with a fork and set aside.
- Prepare the Casserole: Melt the butter in a large skillet over medium heat. Add the chopped leeks and onion. Sauté for about 5-6 minutes until they become translucent and soft. Add the minced garlic and sliced mushrooms to the skillet.
- Cook for an additional 5-6 minutes or until the mushrooms are tender and any liquid they release evaporates. Stir in the dried thyme, sage, cayenne, salt, and pepper. Cook for another minute. Remove from heat, and add the dried fruit (if using).
- Assemble the Casserole: In a large mixing bowl, combine the cooked wild rice, roasted butternut squash mixture, and the sautéed leek and mushroom mixture. Mix well to distribute the ingredients in an even layer. Transfer the mixture to a greased casserole dish.
- Add Cheese and Bake: Sprinkle the shredded Gruyere cheese over the top of the casserole. Cover the casserole dish with aluminum foil. Bake the casserole in the preheated oven at 350°F (175°C) for about about 15 minutes or until the cheese is melted and bubbly.
- Serve: Remove the casserole from the oven and let it cool slightly before serving. Serve the butternut squash casserole warm as a comforting and flavorful vegetarian dish!
Notes
- Cut the butternut squash into uniform cubes so the pieces roast evenly.
- Spread the squash in a single layer on the baking sheet so it can roast evenly and develop lightly caramelized edges.
- Rinse the wild rice before cooking as directed in the recipe.
- Cook the mushrooms until their liquid evaporates before combining them with the other casserole ingredients.
- Let the casserole cool slightly before serving so it is easier to portion and serve.
Nutrition
Nutrition information is automatically calculated, so should only be used as an approximation.
I can only eat a few kinds of cheese due to dietary restrictions (food triggered migraines). Monterey Jack and Parmesan (Iโm so sorry – I donโt know the correct Italian spelling) are two of the ones I know I can eat. Would either of those work? I donโt know if Gruyรจre would give me migraines and itโs a gamble that is sometimes not worth the risk of being out of commission for a few days.
Hi! Yes! Those variations work great. I am sorry about your migraines.
All the taste of fall in one beautiful dish!!