This Broccoli Cheese Casserole is a cheesy, delicious side dish or vegetarian main entree! No need to make a roux sauce with this recipe, so it's super easy to make. But it still has the creamy cheesiness we loved as a kid. Perfect for family weeknight dinners!
If you prefer to use rice, swap in cooked rice for the quinoa.
When kids go back to school, we fall in a pattern where dinner is squeezed between school, work, and kids' activities. That's when dishes like this broccoli cheese casserole are life savers. It checks all the boxes:
☑️ Can I assemble it ahead and just slide it into the oven when I get home?
☑️ Are the ingredients standard, basic ingredients I'm likely to have on hand?
☑️ Does it deliver enough protein to count as a main dish?
- ❤️ Why you'll love this recipe
- 🧅 Ingredients + Notes
- 🔪 Recommended Equipment
- 📝 Instructions Overview
- ⏰ Tips to Simplify and Save Time
- 👩🍳 Preparation Tips
- 💡Ideas for Possible Variations
- 🥩 For the Meat Eaters at the Table
- 🍽 Side Dish Ideas
- 📇 More Casseroles You Might Like
- Broccoli, Cheese and Quinoa Casserole (Recipe)
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❤️ Why you'll love this recipe
- Easy recipe that eliminates making a roux sauce.
- Great vegetarian main dish thanks to protein packed quinoa.
- Easy to add chicken for meat eaters at the table.
- Uses ingredients you probably have on hand.
- Great way to get kids to eat more veggies!
🧅 Ingredients + Notes
- Yellow onion - white onion if fine too, but red onion is too sweet.
- Garlic - either garlic cloves or garlic paste in a tube.
- Broccoli - I use fresh broccoli and haven't made it with frozen broccoli.
- Cooked quinoa
- Milk - either 2% or whole milk is fine.
- Dijon mustard
- Melty cheese - Fontina, Monterey Jack and Cheddar cheeses all work great in this recipe.
- Panko breadcrumbs - plain or with a Gremolata twist.
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📝 Instructions Overview
Detailed instructions for making this broccoli cheese casserole are in the recipe card below, but here's an overview!
Make the quinoa. If you don't already have cooked quinoa on hand, make it first and set it aside for cooling.
Sauté. Sauté the onions, garlic and broccoli until the onions are softened. Add the cooked quinoa. Transfer to a baking dish to cool.
Whisk. Whisk together the milk, eggs and mustard. Fold in the grated cheese with a spatula. Pour over the cooled broccoli and quinoa.
Make the breadcrumb topping. Sauté the breadcrumb topping, and spread evenly over the casserole.
Bake. Bake for 30 minutes.
⏰ Tips to Simplify and Save Time
- Purchase broccoli already cut up. If your market carries it, these bags will be in the produce department.
- Make the quinoa ahead of time, and store in a container in the refrigerator for up to 5 days.
- Some markets sell frozen cooked quinoa in their freezer cases. It only needs to be steamed for a few minutes to be ready to use.
- Cut the broccoli into smaller pieces, so that it will cook faster.
- Assemble the casserole ahead, except for the breadcrumb topping. Cover with plastic, and keep in the refrigerator for up to 2 days. Bring it back to room temperature before baking.
- Make the breadcrumb topping ahead and store in a jar in the refrigerator for up to 2 weeks.
- Make the entire casserole ahead, cover and refrigerate for up to 3 - 4 days. Or store in an air-tight, freezer safe container and freeze for up to 6 months.
👩🍳 Preparation Tips
Be sure to cool off the broccoli and onion before pouring the egg and milk batter over the top. If they're too hot, the eggs may want to curdle (scramble) up a bit.
💡Ideas for Possible Variations
Swap out quinoa for rice.
Top with French Fried Onion Rings instead of breadcrumbs.
🥩 For the Meat Eaters at the Table
Add 1 ½ cups of roast chicken to the casserole or serve it on the side. If you add the chicken to the casserole, increase the milk and cheese by around 25 percent.
🍽 Side Dish Ideas
Air Fryer Potatoes are a great side for so many main dishes, and are a favorite in our house. If you don't have an air fryer, just roast in a 400˚F oven until tender.
Freshly baked bread is always a hit. If you're interested in making a yeasted bread, these Parmesan and Garlic Rolls are irresistible, as is this Aglio e Olio Pizza Bread. Or make this Cheesy Beer Bread with Quinoa, Millet and Jalapeño Peppers.
Fried onion rings - I don't have a recipe for them, but they'd be great with this casserole.
📇 More Casseroles You Might Like
Want even more vegetarian and vegan dish ideas? I can help you. I have three newsletters for different topics: 1) Vegetarian Recipes, 2) Vegetarian Meal Plans, and 3) Vegetarian Tips for helping you to move to a more vegetarian diet. Choose which newsletters are most relevant to your lifestyle and you'll also get my 5 SECRETS TO FUSS-FREE VEGETARIAN DINNERS.
Broccoli, Cheese and Quinoa Casserole (Recipe)
- 3 tablespoons extra virgin olive oil
- 1 cup yellow onion finely diced
- 5 cloves garlic minced, divided
- 1 teaspoon kosher salt divided (or ½ teaspoon table salt)
- 3 cups fresh broccoli chopped into small bite-sized pieces
- 2 cups cooked quinoa
- 2 large eggs
- 1 cup 2% milk or whole milk
- 1 tablespoon Dijon mustard
- 1 ½ cups grated fontina cheese, or other melty cheese such as Monterey Jack or cheddar cheese
- 2 tablespoons unsalted butter
- ½ cup Panko bread crumbs
- Preheat the oven to 350˚F.
- Note: if you don't have cooked quinoa on hand, start it first.
- In a large sauté pan, heat the oil over medium-high heat. Add the onions, and sauté until the onions are softened, about 10 minutes. Add 3 cloves of the minced garlic, ½ teaspoon kosher salt and the broccoli. Sauté for another 5 minutes. Add the quinoa and toss. Transfer it all to an 8" X 8" casserole pan, and spread to even out.
- In a large bowl, whisk together the eggs, milk, mustard, and remaining salt. Fold in the cheese, and pour over the broccoli mixture in the casserole dish Gently toss with a spoon to coat, and to evenly distribute the grated cheese.
- Pro-tip: If the broccoli-quinoa mixture isn't cooled a bit, there is a serious risk of curdling (scrambling) the eggs when the mixture is folded into the liquid.
- Melt the butter in a small skillet over medium heat. Add the remaining garlic and sauté for 1 minute. Add the Panko bread crumbs and a pinch of kosher salt. Sauté until the bread crumbs turn a golden brown, tossing them occasionally with a rubber spatula. Sprinkle over the top of the casserole. (These flavored breadcrumbs can be made ahead and refrigerated for up to a month.)
- Bake for 30 minutes.