Broccoli and cauliflower are generously coated in a creamy white sauce, topped with cheese and bread crumbs, then baked until bubbly, melty and golden brown. This cheesy broccoli cauliflower bake is sure to be a favourite veggie side for Sunday supper or special occasion meals. So easy and ultra comforting!

Cheesy baked broccoli and cauliflower in a dish next to some fresh chives.

Are you a fan of veggies?

How about cheese?

Well, this vegetable au gratin recipe is for you!

“Au gratin” all the things, I say!

Au gratin is just a fancy way of saying covering something in bread crumbs and cheese and baking. Ain’t nothing wrong with that, if you ask me.

I mean, veggies are delicious on their own, but cover them in a creamy, cheesy sauce, top with more cheese and panko and bake until bubbly, melty and golden brown? Oh yeah!

This broccoli cauliflower au gratin (or broccoli cauliflower bake) is technically a veggie side, but I could honestly devour a whole bunch and call it dinner (just like scalloped potatoes).

Why We Love This Broccoli Cauliflower Bake

It’s simple to prepare and made with some humble ingredients.
It’s chock-full of cruciferous veggies.
This veggie side is such a great way to get people to eat their veggies, especially since it’s covered in a yummy cheese sauce!
Of course, it tastes delicious!

How To Make It

Full details are in the recipe card below, but here are the basics:

Start by steaming your florets just to take a little of the bite (crunch) out of them. You definitely don’t want them fully cooked here.
Meanwhile, make your flour roux (similar to the one you’d make when preparing cod au gratin or mac and cheese). In a saucepan, melt some butter, whisk in flour to form a paste and cook for a little.
Gradually whisk in milk and cook until everything is nice and thick and easily coats the back of a spoon. You can add your seasonings at this point too.
Off heat, mix in some shredded cheese.
Coat the florets with your sauce mixture.
Pour into a greased baking dish.
Cover with more cheese and some panko bread crumbs.
Bake until bubbly, melty and straight-up delicious!

Collage of steps to make a vegetable au gratin recipe with broccoli and cauliflower.

A whisk dripping with white sauce into a saucepan.

Once everything is baked, crack into that melty, crispy top layer and dig in.

Serving spoon scooping up some cheesy broccoli cauliflower bake from a dish.

Serve yourself a big portion and maybe go back for seconds (I know I do). This broccoli cauliflower bake is quite hard to resist!

Broccoli cauliflower bake in a dish with a serving spoon resting in it after some has been removed.

Tips and Variations

A mixture of cheese is used in this broccoli cauliflower bake. You can use a good quality store-bought shredded cheese blend or, even better, grate your own. For convenience, the shredded blend allows you to use a variety of cheese without having to purchase a full block of each. However, if you prefer to grate your own you can use a combination of your favourites or all mozzarella or provolone, for example.
Use what cheese you enjoy best. Just pick a good melting cheese (or cheeses), liked cheddar, low moisture mozzarella, provolone, asiago and/or Gouda. You can also add some parmesan for extra flavour.
Cut your florets into roughly equal-sized pieces so they cook evenly.
If you have slightly more broccoli than cauliflower (or vice versa), no worries. You basically want about 8 to 9 cups of florets or about 1.5 pounds worth.
The florets still have a little texture after everything is cooked. If you want them to be a little softer, you can steam them a little more before baking.
Instead of steaming, you can easily boil the florets. If boiling, give them a little shock in cold water afterwards (to stop the cooking process before they’re baked).
Garlic powder and onion powder are used here but you can totally cook some garlic cloves and minced onion instead.

Close-up of cheesy broccoli cauliflower bake in a dish.

More Veggie Side Dishes

If you make this vegetable au gratin recipe, please leave a comment below!

Cheesy baked broccoli and cauliflower in a dish.

Broccoli Cauliflower Bake (Vegetable au Gratin)

Dawn | Girl Heart Food

4.91 from 11 votes

Print Recipe Save Recipe

Prep Time 10

Cook Time 55

Total Time 1 5

Course Side Dish

Servings 6 servings

Ingredients

4 to 4.5 cups broccoli florets, about 1 small head or ¾ pound
4 to 4.5 cups cauliflower florets, about half a large head or ¾ pound
⅓ cup unsalted butter, divided (5 tablespoons)
⅓ cup all-purpose flour
2 cups whole milk
1 teaspoon garlic powder
¾ teaspoon salt, or to taste
½ teaspoon onion powder
½ teaspoon freshly ground black pepper
¼ teaspoon ground nutmeg
6 ounces shredded mozzarella, provolone, Parmesan, Asiago and/or cheddar, divided, about 1.5 cups (see "Notes" below, Point "1")
2 to 3 tablespoons unseasoned panko bread crumbs
Chopped chives or green onion, garnish to taste (optional)

Instructions

Preheat oven to 400 degrees Fahrenheit.
Meanwhile, place broccoli and cauliflower florets in a steamer basket (one that will fit over the pot that you will be using). Next, place a few inches of water in a pot and place the steamer basket over it. Bring water to a boil, cover veggies with the steamer basket lid and steam veggies for 6 to 8 minutes or until just tender crisp. Set aside.
Note: The veggies will soften a little as they bake, but still have a little bite/crunch. If you want them more well done, steam for a little longer before baking.
Then, in a heavy-bottomed saucepan over medium heat, melt ¼ cup (or 4 tablespoons) of butter.
Whisk in flour to form a paste and cook, stirring, for 1 to 2 minutes.
About ¼ cup at a time, whisk in milk. Keep stirring/whisking until thickened and the mixture coats the back of a spoon. Don't add more milk until the previous batch has thickened. This could take about 8 to 10 minutes until your sauce is made.
Stir in garlic powder, salt, onion powder, black pepper and nutmeg.
Off heat, stir in ½ cup (2 ounces) of the shredded cheese and mix until incorporated.
Stir in broccoli and cauliflower florets, stirring to coat in the sauce.
Grease a 9 to 10-inch baking dish (or a baking dish of roughly the same size) with remaining 1 tablespoon of butter.
Pour in broccoli/cauliflower mixture and spread out into an even layer.
Top with remaining 1 cup (or 4 ounces) of shredded cheese and bread crumbs.
Bake for 35 to 40 minutes or until bubbly and the cheese has melted.
Garnish, if desired, with freshly chopped chives. Serve and enjoy!

Notes

A mixture of cheese is used in this broccoli cauliflower bake. You can use a good quality store-bought shredded cheese blend (I used an Italian-style cheese blend, which was a combination of provolone, mozzarella, parmesan and asiago) or, even better, grate your own. For convenience, the shredded blend allows you to use a variety of cheese without having to purchase a full block of each. However, if you prefer to grate your own you can use a combination of your favourites or all mozzarella or provolone, for example.
Use what cheese you enjoy best. Just pick a good melting cheese (or cheeses), liked cheddar, low moisture mozzarella, provolone, asiago and/or Gouda. You can also add some parmesan for extra flavour.
Cut your florets into roughly equal-sized pieces so they cook evenly.
If you have slightly more broccoli than cauliflower (or vice versa), no worries. You basically want about 8 to 9 cups of florets or about 1.5 pounds worth.
The florets still have a little texture after everything is cooked. If you want them to be a little softer, you can steam them a little more before baking.
Instead of steaming, you can easily boil the florets. If boiling, give them a little shock in cold water afterwards (to stop the cooking process before they’re baked).

A note on times provided: appliances vary, any prep and/or cook times provided are estimates only.

Keyword baked vegetables, broccoli and cauliflower cheese bake, cheesy vegetables, vegetable au gratin

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