Move over au gratin potatoes: a new cheesy casserole is stealing the show. And it’s healthy! This broccoli and cauliflower casserole is as cheesy and delicious as any mac n’ cheese, except full of veggies. Our wonder blender cheese sauce packs in flavor AND nutrition with a hidden ingredient for added protein and fiber! 

This cheesy broccoli and cauliflower casserole is a huge win in my book. I downed it as if it were a heaping plate of homemade mac n’ cheese without even really realizing I was eating a hefty serving of veggies! It’s seriously comforting and delicious. And nutritious!

The other win? It’s easy! Aside from the veggies taking their time to roast, the cheese sauce comes together super easily! In an earlier version of this recipe I made a roux base for the sauce, which is great and all, but it’s not the quickest or easiest technique. So I was determined to find an easier and, if possible, healthier way.

…And I did!

Healthy blender cheese sauce

Where do I start with this sauce? I love that it’s made in the blender. Seriously so easy! And I love what’s in it… cheese and a secret ingredient!

Okay, okay, here it is. The secret ingredient in this fantastic cheese sauce is… beans! Cannellini beans, to be precise. They thicken the sauce nicely and add some protein!

With protein, this dish can now serve as either a side dish or a vegetarian main. Though, I would likely add another cup of beans to bulk up the protein content if I were serving it as the main course, personally.

The how-to of this sauce is simple. Rinse and drain the beans, then put all the sauce ingredients into the blender (except a little cheese to use on top of the casserole). Blend until smooth. That’s it!

Broccoli and Cauliflower Casserole

But I got ahead of myself. Starting at the beginning, you’ll need to get your oven heated to 400* F. While it’s heating, chop your broccoli and cauliflower.

Broccoli is pretty straightforward to cut, but I have always dreaded cauliflower. I feel like it always becomes a mess and it’s tough to get past the leaves to cut properly. So I figured out a better way! If you, too, want to find a better way to cut cauliflower, here’s the post I just wrote on the easier way to cut cauliflower.

You’ll want to cut your cauliflower a little smaller than the broccoli for this recipe. Not minced or anything, but just give it a few good chops so that the pieces are small enough to come together well in casserole form.

Tossing the veggies in a tablespoon of olive oil in the casserole dish you plan to use makes for less mess and greases your pan at the same time. Sprinkle on a little salt and pepper and then slip them into the oven for 20 minutes.  I recommend mixing them about halfway so that they get evenly roasted since they’re not in a single layer.

This is when you blend up your sauce, mentioned above. Mix the sauce into the veggies once they’ve roasted for 20 minutes. Then top with a bit of remaining cheese and place in the oven again. I cooked mine for about 25 more minutes, but I like my veggies pretty firm so you may want to add another five minutes or so if you like yours soft.

Try this cheesy broccoli and cauliflower casserole with your family and see how it goes! Are your kids more likely to eat cooked veggies covered in cheese sauce?