Broccoli is probably the favorite vegetable in our house. We love it roasted, sautéed, in stir-fries, and in this broccoli casserole where it stars in its very own show! What I love about this casserole is that it’s substantial enough to qualify as a vegetarian main course (please make sure to use vegetable broth!) and dazzling as a side. Plus, leftovers are a total delight, even just warmed in the microwave.

I am not a huge fan of using canned soup in recipes, though I certainly appreciate how it solves a problem in a pinch. However, in this recipe, a creamy sauce made from broth and dairy is thickened with a flour and butter roux, which provides the same level of body and richness without any additives. It really doesn’t take much more time, and the improved flavor is worth every minute and every bite.

Serve this casserole alongside Roast Chicken or herbed chicken legs baked in the oven with a side of Cornbread for a complete dinner. It’s also an excellent option for your Thanksgiving table sides and really nice with Roasted Turkey.

This cheesy Broccoli Casserole is hearty enough to be a vegetarian main course, but also a substantial side for cold weather dinners and holidays.

Simple Vegetarian Casserole for the Holidays

This casserole would be happy at home in the middle of any holiday feast. Great for Thanksgiving, Christmas, Easter, or any time you are looking for a slightly decadent vegetable casserole to add to a menu. It could also be a lush main dish any night of the week, especially welcome during cooler weather. A green salad would be a nice counterpoint to the richness of the creamy casserole.

Broccoli Casserole Ingredients

Once you have the broccoli and mushrooms in hand, you may well find that the rest of the ingredients for this casserole are already in your pantry or fridge!

• Butter – I use unsalted butter so I can better control the level of salt in the dish. Butter adds wonderful richness and flavor. It also forms the base of the roux, which thickens the sauce.
• Flour – A small amount of flour blended into the butter allows the sauce to thicken. If you wanted to skip it for a gluten-free broccoli casserole, you could — the sauce will still be nice and creamy, just not as thick. Or use gluten-free flour.
• Whole milk or half-and-half – This is where the creaminess begins. Whole milk will make for a lighter casserole, while half-and-half will be a bit more decadent.
• Chopped onions and mushrooms – There is no savory casserole that can’t be improved by the addition of onions and/or mushrooms. Use any mushrooms you like, from button mushrooms to cremini to shiitake or wild mushrooms. For the holidays, I like to use an assortment of wild mushrooms to make the casserole even more special.
• Broccoli – Cut the broccoli into florets. You can make them on the smaller size for bite-sized forkfuls of broccoli casserole or keep them a bit larger and let people cut up larger chunks with a knife and fork.
• Chicken or vegetable broth – Make sure to use vegetable broth if you want to keep this casserole vegetarian.
• Sour cream – You can use reduced-fat sour cream if you are trying to keep the fat and calories a bit more restrained, but I am a fan of full-fat dairy products. I’d go for a smaller portion of a richer dish every time.
• Shredded cheddar cheese – You can use yellow, orange, or white cheddar…whatever you prefer. And you can use anything from mild to very sharp.

Variations and Substitutions

• Broccoli and Rice Casserole: One variation on this casserole is to add 1 1/2 cups of cooked rice along with the white sauce, which will give the casserole a bit more heft and density.
• Chicken and Broccoli Casserole: If you want to make this into a chicken and broccoli casserole, you can add 2 cups of shredded or diced cooked chicken when you add the white sauce to the pan with the broccoli. Obviously, this is no longer a vegetarian casserole once you add the chicken.
• Other melting cheeses could be substituted for the cheddar, like Monterey Jack, fontina, or provolone. Each of these cheeses will add its own distinct flavor to the casserole. If you wanted to replace 1/2 cup of the grated cheddar with Parmesan, that will add a nice nutty flavor.
• You could use shallots or leeks as a substitute for the onions.

How to Make Broccoli Casserole

1. Prepare the oven and casserole dish: Preheat the oven to 375 F. Butter a shallow 3-quart casserole dish.
2. Make the sauce: Melt 3 tablespoons of the butter in a medium saucepan over medium heat. Sprinkle in the flour, season with salt and pepper, and whisk until the mixture is smoothly blended and starts to turn a light golden color. Gradually add the milk, whisking constantly. Continue to whisk often until the mixture just comes to a simmer, then whisk frequently for another 4 minutes, until the sauce has thickened. Adjust the heat so the mixture stays at a simmer.
3. Sauté the onions and mushrooms: Meanwhile, in a large skillet with a lid, heat 2 more tablespoons of butter over medium heat until melted. Add the onions and mushrooms and sauté for about 8 minutes until the vegetables are brown and any liquid that gets released evaporates. Season with salt and pepper. Stir the mushroom mixture into the white sauce.
4. Steam the broccoli: Return the skillet to medium-high heat and add the broccoli and the broth. Bring the mixture to a simmer, then cover the pan and steam the broccoli for 4 minutes until almost tender.
5. Combine the casserole ingredients: Pour the white sauce into the pan with the broccoli and remaining broth (there should be about 1 1/2 cups left in the pan) and stir to combine. Add the sour cream and the cheese and stir to blend well. Transfer the mixture to the prepared baking dish and spread it out evenly.
6. Bake and serve: Bake for 30 minutes until bubbly and golden brown on top. Serve hot.

FAQs

What to Serve With Broccoli Casserole

Cajun Roasted Turkey

Cornish Hens

Maple-Roasted Butternut Squash

More Broccoli Recipes

• Parmesan Roasted Broccoli
• Broccoli Salad
• Broccoli Cheddar Soup
• Salmon, Potato, and Broccoli Sheet Pan Supper
• Shrimp and Broccoli Stir Fry with Udon Noodles