Brussels Sprouts Casserole with Crispy Onions

What side dishes come to mind when you think about holiday dinners? Stuffing, potatoes, green bean casserole. In fact, green bean casserole has almost become synonymous with holiday dinners. And I’m sure I’m in the minority when I say that I really, really don’t like green bean casserole. It’s not necessarily the flavor that I don’t like. I just don’t care for cooked green beans. I like them crispy and crunchy, right out of the garden, dipped in ranch dressing. Cook them and you lose me.

So I wanted to come up with something that honors the earthy flavors of a traditional green bean casserole and incorporates that salty, crunchy fried onion topping – but without the green beans. I honestly love this Brussels Sprouts Casserole with Crispy Onions so so much – it really hits on all cylinders. It’s warm and creamy with that unforgettable fried onion topping, and so much better with brussels sprouts.

How to make this Brussels Sprouts Casserole

You’re going to blanch the brussels sprouts before baking them into the casserole, which will mellow them out significantly and make them nice and tender. To blanch a vegetable, you simply put it in boiling water for 1-2 minutes, then immediately plunge it into a bowl of ice water. By doing this, you’ll allow the flavors of the mushrooms and thyme to really shine.

The creamy sauce comes together in one skillet. Start by making a roux of flour, garlic and butter, then adding the milks. Let it thicken, and then pour it over your sprouts and mushrooms. Baked up all together, they make for a rich, earthy flavor profile.

The Crispy Onions

But the best part of this Brussels Sprouts Casserole with Crispy Onions is the topping. It’s too bad the topping isn’t all throughout, because you really want to get some of that salty crunch in every bite. But keeping them crunchy is easier said than done.

They have to go on top in just the last few minutes of baking, just to get them browned. For best results, you’ll want to serve this casserole immediately. Since the onion topping will not stay crunchy in the fridge, if you want to reheat it the next day, scrape off the remaining onions, reheat the casserole and add new fried onions in the last few minutes of baking.

This casserole has become a new family tradition for us, one that even the kids enjoy – and that’s saying something! I hope it will be a welcome new addition to your holiday table. Enjoy!

Brussels Sprouts Casserole with Crispy Onions

Tender brussels sprouts in a creamy, garlicky sauce, baked until bubbling

Print Recipe Pin Recipe

Prep Time 20 mins

Cook Time 45 mins

Total Time 1 hr 5 mins

Course Side Dish

Cuisine American

Servings 12

Ingredients

  

1x2x3x

• 2 lbs. brussels sprouts
• 1 lb. cremini mushrooms cleaned and sliced
• 1/2 lb. button mushrooms cleaned and sliced
• 6 Tbsp. unsalted butter
• 1 tsp. salt
• 4 sprigs of thyme
• 4 cloves garlic minced
• 3 Tbsp. flour
• 1 1/2 cups whole milk
• 1 1/2 cups half & half
• 2 cups French’s fried onions

Instructions

 

• Preheat oven to 400 degrees.
• Rinse and dry brussels sprouts. Trim the ends and cut sprouts in half. Bring a large pot of salted water to a boil. Blanch brussels sprouts for 5 minutes, then immediately drain and plunge into a large bowl of ice water. Drain and dry with paper towels.
• Saute the mushrooms and thyme in 4 tbsp. of the butter until very dark and tender, about 12-15 minutes. Remove with a slotted spoon, discard the thyme and place onto a separate plate. Season with salt and pepper.
• In the same pan, add the remaining 2 tbsp. of butter. Melt the butter over medium heat. Add the flour, garlic and salt. Whisk constantly until it starts to bubble. Whisk in the milk and half-and-half. Cook, whisking, until thickened.
• Place mushrooms and brussels sprouts into a 2-quart baking dish and pour sauce over top. Cover with foil. Bake for 20 minutes or until sauce is bubbly. Uncover and continue to bake another 20 minutes or until the top is browned. Top with onions and bake another 2-3 minutes. Serve immediately.

Keyword vegetarian

Tried this recipe?Let us know how it was!