Go Back
+ servings
Print Recipe
5 from 3 votes

Brussels Sprouts Gratin

If you're looking for a change from the go-to roasted version then this creamy Brussels Sprouts Gratin is for you! Brussels sprouts and carrots get paired with smoky bacon and a cheesy mustard sauce for an over the top, crunchy delish side dish.
Prep Time15 mins
Cook Time20 mins
Total Time35 mins
Course: Side Dish, Vegetable
Cuisine: American, Western
Keyword: Brussels sprouts casserole, Brussels sprouts gratin
Servings: 6
Calories: 320kcal


  • 1 1/2 lbs Brussels sprouts trimmed and halved
  • 2 carrots peeled and sliced (about 2 cups), or baby carrots
  • 6 slices bacon chopped
  • 1 tbsp butter
  • 1 medium red onion diced (about 1 cup)
  • 1/2 tsp salt
  • 1/2 tsp black pepper
  • 3 cloves garlic minced
  • 1 tbsp flour
  • 1 cup Parmesan cheese 4 oz, shredded
  • 1 cup heavy cream or half and half
  • 1 tbsp dijon mustard or coarse ground mustard
  • 1/2 cup Panko bread crumbs


  • Preheat oven to 400°F. Coat a 1 1/2-quart casserole or au gratin dish with oil or coking spray.
  • In a large saucepan of heavily salted boiling water, cook Brussels sprouts and carrots for 5 minutes or until fork tender. Drain, discarding water, and return vegetables to saucepan. Set aside.
  • In a large skillet over medium heat render bacon until crisp. Transfer bacon to paper towels to drain, reserving the bacon fat in skillet. Add red onion to skillet and sauté for a minute. Add garlic, kosher salt and pepper and sauté another minute. Stir in flour and cook for another minute.
  • Toss onion mixture and crisp bacon with boiled vegetables in saucepan. Stir in half of the cheese, tossing to coat. Spoon Brussels sprouts mixture into the prepared casserole dish.
  • In a small bowl whisk together the heavy cream and mustard. Pour evenly over Brussels sprouts mixture. Sprinkle Panko and remaining half of cheese over Brussels sprouts mixture. Bake for 20 minutes or until mixture is bubbling and topping is golden brown.


  1. Immediately drain the Brussels sprouts and carrots to best keep the bright color.
  2. I often times use the baby carrots instead of large so I don't have to peel them!
  3. Feel free to use pepper bacon or even pancetta instead of bacon.
  4. You may substitute shallots for th ered onion.
  5. I also use asiago, Gruyère or a mixture of these cheeses instead of the parmesan,  they're a great substitute.
  6. A coarse grain mustard (like my homemade version) is a great substitute for the dijon.


Calories: 320kcal | Carbohydrates: 22g | Protein: 15g | Fat: 20g | Saturated Fat: 10g | Cholesterol: 46mg | Sodium: 748mg | Potassium: 660mg | Fiber: 6g | Sugar: 5g | Vitamin A: 4584IU | Vitamin C: 100mg | Calcium: 310mg | Iron: 2mg