There’s just something about a bubbling, cheesy casserole that makes you feel right at home, isn’t there? Whether you’re gathering around the table on a cozy weeknight or looking for a hearty meatless dish to share at a potluck, this Cauliflower and Broccoli Veggie Casserole hits all the right notes. It’s rich and creamy, loaded with roasted veggies, and finished off with the most irresistible crispy topping. Honestly, even the pickiest eaters in my house end up asking for seconds.

This recipe came about on a rainy Sunday afternoon when I had half a head of cauliflower, a few florets of broccoli, and a serious craving for something warm and cheesy. I didn’t want another pasta bake or a soup—I wanted that classic casserole comfort but with a fresh twist. That’s how this roasted veggie version was born. It’s now a staple at our dinner table, especially when we need a vegetarian main that still feels indulgent and satisfying.

Let’s talk about what makes this casserole so special. First, we’re roasting the vegetables instead of steaming or boiling them. This step makes a big difference—it brings out a nutty depth in both the cauliflower and broccoli, giving them a little crispy edge and so much more flavor. Then, we coat everything in a creamy homemade cheese sauce that melts into every crevice. And to top it off? A buttery, crunchy panko-Parmesan crust that turns beautifully golden in the oven.

This dish is great as a side—hello, holiday dinners!—but hearty enough to stand on its own as a main. It also reheats like a dream, which means leftovers are never a problem (in fact, I think they might be even better the next day).

Alright, let’s get into the kitchen and start with the first key step: roasting our vegetables.

STEP 1: ROAST THE VEGETABLES

This step sets the tone for the entire casserole. Roasting gives the cauliflower and broccoli a caramelized edge and keeps them from turning mushy once baked with the cheese sauce.

You’ll need:

• 1 medium head of cauliflower, cut into florets

• 1 medium head of broccoli, cut into florets

• 2 tablespoons olive oil (or butter, if you prefer a richer flavor)

• Salt and pepper to taste

• 2 garlic cloves, minced (totally optional, but adds a lovely flavor kick)

Instructions:

1. Preheat your oven to 400°F (200°C).
   A hot oven ensures your veggies get that nice golden roast.

2. Toss your florets.
   In a large mixing bowl, combine your cauliflower and broccoli with the olive oil (or butter), a good pinch of salt and pepper, and garlic if you’re using it. Make sure everything is evenly coated. You want that oil to touch every little crevice—it’s what helps things crisp up!

3. Spread them out.
   Line a large baking sheet with parchment paper and spread the veggies in a single layer. Give them some space—if they’re too crowded, they’ll steam instead of roast.

4. Roast for 15–20 minutes.
   You’re looking for slightly tender florets with a bit of browning on the edges. Depending on your oven, you might want to flip them halfway through to make sure everything cooks evenly.

Once they’re done, set them aside and resist the urge to snack on them all before they make it to the casserole dish—I’m speaking from experience here.

STEP 2: MAKE THE CHEESE SAUCE

This cheese sauce is thick, creamy, and coats the vegetables like a dream. You can stick with classic cheddar, or get a little fancy and throw in some mozzarella or Parmesan for extra flavor depth.

You’ll need:

• 2 cups shredded cheddar cheese (feel free to mix in mozzarella or Parmesan)

• ½ cup milk (dairy or almond milk works well)

• 2 tablespoons all-purpose flour

• 1 teaspoon Dijon mustard (optional, but adds a little zing)

• ¼ teaspoon nutmeg (optional, but a lovely warm touch)

Instructions:

1. Whisk the flour and milk.
   In a medium saucepan over medium heat, add the flour and milk. Whisk constantly for 1–2 minutes until the mixture thickens slightly. You’re creating a simple roux here that gives the sauce body without needing butter or cream.

2. Melt in the cheese.
   Once the base is smooth and slightly thickened, reduce the heat to low. Gradually add your shredded cheese in batches, stirring constantly so it melts evenly. You’ll end up with a creamy, velvety sauce.

3. Add the extras (if using).
   Stir in the Dijon mustard and nutmeg. Dijon adds a subtle tang that balances the richness, and nutmeg gives a hint of warmth that’s especially great for fall and winter meals. Totally optional—but highly recommended.

4. Remove from heat and set aside.
   You don’t want to overcook the sauce. Once everything’s smooth and melty, take it off the heat. It will thicken a bit more as it stands.

STEP 3: ASSEMBLE THE CASSEROLE

Now comes the fun part—putting it all together! Think of it like layering flavor after flavor into a dish that’s destined for the dinner table spotlight.

Instructions:

1. Grease your baking dish.
   Use a 9×13-inch baking dish and give it a light coating of butter or nonstick spray.

2. Layer the roasted veggies.
   Spread your roasted cauliflower and broccoli evenly across the bottom of the dish. Try to keep it in one layer so everything gets a good coating of sauce.

3. Pour the cheese sauce.
   Gently pour your warm cheese sauce over the veggies. Use a spatula or the back of a spoon to spread it evenly. Make sure it’s reaching all the nooks and crannies—this is what transforms the casserole from a veggie dish to pure comfort food.

STEP 4: PREPARE THE TOPPING

This might be my favorite part. The contrast of the golden, crunchy topping with the creamy interior is what makes this casserole so satisfying.

You’ll need:

• ½ cup panko breadcrumbs

• 2 tablespoons melted butter

• ¼ cup grated Parmesan cheese

Instructions:

1. Mix it up.
   In a small bowl, combine the panko breadcrumbs, melted butter, and grated Parmesan cheese. Stir it all together until the crumbs are evenly coated and the cheese is mixed in.

2. Top the casserole.
   Sprinkle the breadcrumb mixture over the cheese-covered vegetables. Try to cover as much surface area as you can for an even crunch with every bite.

STEP 5: BAKE TO PERFECTION

By now, your kitchen probably smells amazing, and we’re just one step away from golden, bubbly, casserole glory.

Instructions:

1. Lower the oven temperature.
   Reduce the oven to 375°F (190°C). We roasted the veggies hot, but now we want to bake everything gently to meld the flavors together.

2. Bake for 20–25 minutes.
   The cheese sauce will bubble up slightly around the edges, and the topping will turn golden brown. If your topping needs a little extra crisping, flip on the broiler for the last 1–2 minutes—just keep a close eye on it so it doesn’t burn.

3. Let it rest.
   After removing the casserole from the oven, let it sit for about 5 minutes. This helps everything set just a bit, so it’s easier to serve and even more flavorful.

4. Garnish and serve.
   Sprinkle some fresh chopped parsley on top for a little color and brightness. Serve warm, and enjoy every cheesy, crunchy bite.

CAULIFLOWER AND BROCCOLI VEGGIE CASSEROLE

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• Author: Mark's Recipe
• Total Time: 55 minutes

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Description

This comforting veggie-packed casserole is loaded with roasted cauliflower and broccoli, smothered in a creamy cheese sauce, and topped with a crispy breadcrumb crust. It’s a perfect side or a main for a hearty vegetarian meal.

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Ingredients

Scale 1x2x3x

For the Veggies:

• 1 medium head cauliflower, cut into florets
• 1 medium head broccoli, cut into florets
• 2 tbsp olive oil (or butter)
• Salt and pepper to taste
• 2 garlic cloves, minced (optional)

For the Sauce:

• 2 cups shredded cheddar cheese (or mix with mozzarella/Parmesan)
• ½ cup milk (or almond milk)
• 2 tbsp all-purpose flour
• 1 tsp Dijon mustard (optional)
• ¼ tsp nutmeg (optional)

For the Topping:

• ½ cup panko breadcrumbs
• 2 tbsp melted butter
• ¼ cup grated Parmesan cheese
• Fresh parsley, chopped (for garnish)

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Instructions

1️⃣ Roast the Vegetables:
Preheat oven to 400°F (200°C).
In a large bowl, toss cauliflower and broccoli with olive oil, salt, pepper, and minced garlic. Spread on a parchment-lined baking sheet.
Roast for 15–20 minutes, until tender and slightly golden. Set aside.

2️⃣ Make the Cheese Sauce:
In a saucepan over medium heat, whisk together flour and milk until smooth. Cook for 1–2 minutes, stirring constantly, until thickened.
Reduce heat to low. Gradually add shredded cheese, stirring until melted.
Stir in Dijon mustard and nutmeg if using. Remove from heat.

3️⃣ Assemble the Casserole:
Grease a 9×13-inch baking dish.
Layer roasted vegetables in the bottom. Pour cheese sauce over the veggies, spreading evenly.

4️⃣ Prepare the Topping:
In a small bowl, combine panko, melted butter, and Parmesan cheese.
Sprinkle evenly over the casserole.

5️⃣ Bake to Perfection:
Reduce oven to 375°F (190°C).
Bake for 20–25 minutes until top is golden and bubbly. For extra crispiness, broil 1–2 minutes at the end, watching carefully.

6️⃣ Serve and Enjoy:
Let rest for 5 minutes. Garnish with chopped parsley and serve warm.

Notes

• Make it ahead: You can assemble the entire casserole a day in advance. Just cover and refrigerate, then bake when ready (add 5–10 minutes extra baking time from cold).
• Cheese choices: For a richer flavor, use sharp cheddar or a blend of cheeses like Gruyère, Swiss, or Monterey Jack. A little blue cheese can also add bold flavor if you enjoy it.
• Texture tip: Roasting the veggies instead of boiling keeps them from becoming soggy and brings out their natural sweetness.

• Prep Time: 15 minutes
• Cook Time: 40 minutes

Nutrition

• Serving Size: 6