Sweet, salty, rich, and smokey, every bite of our Roasted Brussels Sprouts Au Gratin with Bacon is tender and crunchy, making a perfect companion to any holiday meal.
The holidays are no time to skimp and this dish is no exception. Starting with a thick base of perfectly caramelized brussels sprouts, our gratin is made with heavy cream, loads of cheese, and of course, bacon. And the only thing better than bacon is more bacon, so we've topped off our brussels sprout gratin with a crispy topping of breadcrumbs and even more bacon.
Bacon is always a good idea, and when paired with Brussels sprouts they’re an incredible duo that complements one another adding richness and smokiness. It's a flavor combination we use often, whether simply sauteed together, roasted, or in our favorite Brussels Sprout Caesar Salad.
But with the colder than-normal fall, we found ourselves craving something a little warmer and a little more comforting: Enter our Roasted Brussels Sprouts au Gratin with Bacon.
What is Au Gratin?
Au gratin is a French cooking technique in which a breadcrumb and/or cheese topping is browned under a broiler or baked. The classic and most common preparation is Potatoes Au Gratin, however, it can be made using pretty much any vegetable.
Brussels sprouts, bacon, cheese (gruyere or cheddar), Parmesan, olive oil, heavy cream, garlic, bread crumbs, butter, sea salt and freshly ground pepper.
How to Make Our Roasted Brussels Sprouts Au Gratin
Step One | Roast the Brussels Sprouts
Preheat your oven to 425° F and clean the brussels sprouts.
How to Buy and Clean Brussels Sprouts
When shopping for brussels sprouts the freshest ones will still be attached to the stock, but if they are loose, looked for tightly wrapped leaves with very little to no yellowing. They should have a fragrant herbaceous smell.
To clean them, trim the bottom and remove any loose leaves. Place them in a bowl of cold water and allow them to sit for a few minutes. They aren't a dirty vegetable but this will remove any dust that may have collected during their travels. Once clean, place them in a colander to dry or pat them dry with a clean towel.
How to Roast Brussels Sprouts
Brussels sprouts have a sweet nutty flavour and to help accentuate these characteristics we start by roasting the brussels sprouts. Cut the sprouts in half lengthwise and place them in a 9 by 13-inch casserole dish. Drizzle with a couple of tablespoons of olive oil and a liberal sprinkling of salt and pepper. Toss and arrange the brussels sprouts in the pan. To get good caramelization on the sprouts we arrange the sprouts on the bottom of the casserole cut side down in a single layer, and the top brussels sprouts with the cut side facing up. Roast the brussels sprouts in the oven for 30 minutes or until the cut side is browned but the sprouts still vibrant green.
Step Two | Prepare the Bacon
While the brussels sprouts are roasting cook the bacon in a frying pan. You will need about 10 to 12 slices of bacon and can either fry them in one batch or two. If you prefer a perfectly evenly cooked bacon that's super crisp, cook in two batches. Cooking in one batch will give you different textures, which we prefer for this recipe. Once the bacon is cooked how you like, transfer to a paper towel-lined bowl or plate to remove excess grease.
Once the bacon is cool enough to handle, chop it as finely as possible and place in a bowl. There should be about ¾ cup of bacon bits.
Step Three | Make the Gratin Mixture and Breadcrumb Topping
For the gratin mixture, in a medium bowl, mix together 2 cups of grated cheese, ½ cup grated Parmesan, 1 ½ cups heavy cream, ½ cup of the chopped bacon and 2 cloves of finely minced garlic. Season lightly with sea salt and freshly ground pepper and set aside.
For the bread crumb topping, in a separate bowl add 1 ½ cups breadcrumbs, remaining ¼ cups of Parmesan and bacon, and ¼ cup butter. Mash the mixture together to form and crisp type topping and set aside.
Step Four | Assemble the Brussels Sprouts Au Gratin
Once the Brussels sprouts are roasted, remove them from the oven and top with the gratin mixture. Toss everything together until all the ingredients are evenly distributed.
Make it Beautiful: For a more elegant presentation, after mixing the brussels sprouts with the gratin mixture, turn the top layer of brussels sprouts so the caramelized side is facing up before adding the breadcrumb topping.
Step Five | Top and Bake the Gratin
Sprinkle the breadcrumb topping over the Brussels sprouts allowing some of them to peak through. Place in the oven and bake an additional 15 to 20 minutes, until the cheese is bubbling, and the breadcrumb topping is browned and crisp.
- 2 lbs brussels sprouts
- 2 tablespoon olive oil
- sea salt and freshly ground pepper
- 8 oz bacon
- 2 cups grated Gruyere cheese
- ¾ cup grated Parmesan cheese
- 2 cloves garlic finely minced
- 1 ½ cups heavy cream
- 1 ½ cups breadcrumbs
- ¼ cup salted butter room temperature
- Preheat your oven to 425° F.
- Clean, trim and cut the brussels sprouts in half lengthwise. Place in a 9 by 13-inch roasting pan and toss with olive oil, plus sea salt and pepper to taste.
- Arrange the brussels sprouts so the bottom layer of sprouts are cut side down and the top layer of sprouts are cut side up (this is give them nice caramelization). Place in the oven and roast for about 30 minutes, until the flesh is golden browned and almost fork tender.
- While the brussels sprouts are roasting cook the bacon in a frying pan, until cooked through and crisp. Transfer to a paper towel-lined bowl or plate to remove excess grease. Once the bacon is cool enough to handle, chop it as finely as possible and place in a bowl, then set aside.
- For the gratin mixture, in a medium bowl, mix together gruyere cheese, ½ cup grated Parmesan, cream, ½ cup of the chopped bacon and garlic. Season lightly with sea salt and freshly ground pepper and set aside.
- For the breadcrumb topping, combine breadcrumbs, remaining Parmesan and bacon, and butter in a medium bowl until it forms a crisp type topping and set aside.
- Once the brussels sprouts are roasted, remove them from the oven and top with the gratin mixture. Toss everything together until all the ingredients are evenly distributed.
- Sprinkle the breadcrumb topping over the brussels sprouts allowing some of them to peak through. Place in the oven and bake an additional 15 to 20 minutes, until the cheese is bubbling, and the breadcrumb topping is browned and crisp.
- For a more elegant presentation, after mixing the brussels sprouts with the gratin mixture, turn the top layer of brussels sprouts so the caramelized side is facing up before adding the breadcrumb topping.