This vegetarian barbecue quinoa casserole is a perfect weeknight dinner or make-ahead lunch that is packed with plant-based protein and flavor!Jump to Recipe
Remember these delicious vegetarian barbecue stuffed bell peppers? Well, this barbecue quinoa casserole is a lightly inspired variation on that dish. Instead of stuffing individual bell peppers, we will be creating a nutrient-dense bake that is perfect for all your back to school needs. This recipe is filling and easily makes 6-8 servings depending on how hungry you are, so you can rest assured that this quinoa casserole will take you far.
Ingredients for Barbecue Quinoa Casserole
Quinoa: I chose quinoa for this casserole because I absolutely love the way quinoa absorbs the flavors of whatever sauce it’s baked in. As a bonus, it’s a complete plant-based protein and has plenty of fiber.
Bell Peppers: I wanted to create that classic barbecue pizza profile here, so bell peppers were a must.
Red Onions: They will get all crispy and roasted in the oven prior to being added to the casserole and add the most delicious flavor.
Sweet Potatoes: Honestly, sweet potatoes might be my favorite food. In this quinoa casserole, they serve to add texture, flavor, and a dose of healthy carbs. Because who doesn’t love carbs?
Olive Oil: Just a tablespoon to make sure our veggies roast up properly.
Garlic Powder and Fresh Minced Garlic: This recipe calls for garlic powder and fresh garlic. Why? Well, first of all because it’s near impossible to have too much garlic. But more importantly, they serve different functions. The garlic powder is tossed with the peppers, onion, and sweet potatoes prior to roasting. The reason for this is to give the veggies time to marinate in the garlic flavor and absorb all the deliciousness. I also throw some fresh garlic into the quinoa mixture to give the casserole at large well-distributed garlic flavor.
Black Beans: For some delicious plant-based protein, y’all.
Cilantro: To add some herby fresh flavor and round out that barbecue pizza profile.
Salt and Pepper: This is completely to taste and preference. It will really depend on how salty your barbecue sauce is.
Cheese: I like a mixture of both mozzarella and cheddar, but if you only have one on hand, that totally works!
Meal Prep Tips for Barbecue Quinoa Casserole
If you’re looking to get some preparation out of the way ahead of time, here are my recommendations:
- Cook the quinoa ahead of time and store in refrigerator in an airtight container for up to 2 days. You could also buy a pre-cooked frozen package of quinoa.
- Chop bell peppers, red onions, sweet potatoes, and cilantro up to 2 days ahead of time and store in an airtight container in the refrigerator.
- Roast the veggies up to 2 days ahead of time and store in an airtight container in the refrigerator.
- Once the aforementioned steps are completed, combine all components of the casserole mixture and store it in an airtight container in the refrigerator for up to two days. You could even go ahead and top it with the cheese as long as it has an airtight cover.
Customization & Pairing Tips
Here are some fun ideas for making this casserole your own:
- Add some fresh or frozen corn! This would be delicious, especially when corn on the cob is in season.
- If you’re not vegetarian, you could definitely add some shredded or cubed chicken breast.
- To make vegan, simply omit the cheese or use plant-based cheese shreds.
- I love to serve this casserole with additional fresh cilantro and ranch dressing.
A Note on Roasting Your Veggies
It may seem like a hassle, but if you have two sheet pans, definitely use both. Make sure all your veggies are evenly distributed and have breathing room, and you will be rewarded with roasted, caramelized goodness. Additionally, I would encourage you to put the bell peppers and red onions on one sheet pan and the sweet potatoes on another because I find that the peppers and onions often roast more quickly and you can pull them out first if needed.
If you make this barbecue quinoa casserole, be sure to leave a rating and review! This helps Google figure out that this little blog exists and encourages others to give it a try!
Other Easy Dinner Ideas:
Vegetarian Barbecue Quinoa Casserole
- 9×13 Baking Dish
- Cutting Board
- Chef's Knife
- Sheet Pan
- parchment paper
- Medium Pot with Lid
- 1 cup uncooked quinoa
- 2 cups water
- 2 bell peppers diced (any color)
- 1 medium red onion diced
- 1 large sweet potato diced
- 1 tbsp olive oil divided
- ½ tsp garlic powder
- 1½ cups barbecue sauce
- 1 can black beans drained and rinsed
- ½ cup cilantro chopped
- 3 cloves garlic minced
- ½ cup mozzarella cheese shredded
- ½ cup cheddar cheese shredded
- Salt and pepper
- Preheat oven to 400° F and line two sheet pans with parchment paper or silicone mat. Place bell peppers and onions on one sheet pan and sweet potatoes on another. Toss them all with the olive oil, garlic powder, and salt and pepper to taste. Place both pans in the oven on separate racks and roast for 20 minutes. Keep an eye on the peppers and onions, as they may finish more quickly depending on your oven.
- Meanwhile, make quinoa. Put uncooked quinoa, water, and pinch of salt in a medium pot and place on stovetop over high heat. Once it's brought to a boil, reduce the heat to low and cover pot with a lid. Simmer for 15 minutes or until the water has absorbed and the kernel has "popped" and it has a little "tail." Fluff it with a fork.
- Remove veggies from the oven and lower temperature to 375° F. In a large bowl, combine cooked quinoa, roasted veggies, cilantro, garlic, barbecue sauce, and black beans and mix until well-combined. Add more salt and pepper to taste.
- Add quinoa and veggie mixture to a greased 9×13 baking dish and top with the cheese. Bake for 25 minutes or until the cheese is golden brown. Carefully broil at the end to make sure the cheese is extra crispy if desired.
- Let sit and cool for 5-10 minutes before serving. Will keep in an airtight container in the refrigerator for up to 5 days.
Photography by Hope Agresti