Brussel Sprouts Gratin

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This Brussel Sprouts Gratin is not your average gratin.  This delicious side dish is a low-carb wonder perfect for those looking to enjoy a guilt-free indulgence at the dinner table.

Brussels sprouts didn’t always have the best reputation in my household. They were often met with skeptical glances and polite nibbles, but that all changed when I introduced this Brussel Sprouts Au Gratin recipe to the mix.

It’s become a crowd-pleaser that even the pickiest eaters can’t resist. It’s even inspired the whole family to also try my Smashed Brussel Sprouts recipe. 

Whether I am serving a weeknight meal to my family or planning a holiday gathering, finding the perfect side dish to complement the main course is crucial.

Brussels sprouts gratin pairs well with succulent pork roast, roasted meat, chicken, or fish. I plan to serve it alongside my Christmas Chicken and delicious Air Fryer Ham this holiday season.

When you need something that will taste fantastic and steal the show, this is the recipe you need. I’ll walk you through the steps to create this mouthwatering dish that combines the nutty, earthy flavors of Brussels sprouts with the creamy decadence of gratin.

Plus, I’ll share some tips and tricks to ensure your gratin turns out perfectly every time.

Why Make this Brussel Sprouts Casserole Recipe

• It’s low carb – This recipe offers a guilt-free side dish that’s both flavorful and filling for those watching their carb intake. It’s a great choice for anyone following a low-carb or keto diet.
• It’s got delicious flavor –  Brussels sprouts are transformed into a mouthwatering delight when combined with a creamy, cheesy gratin sauce. The rich and savory taste is hard to resist.
• Perfect for make-ahead – Like this Scalloped Corn Recipe, You can prepare Brussels Sprouts Gratin in advance, which makes it a convenient choice for hosting. Simply pop it in the oven before serving to achieve that fresh-from-the-oven appeal.

Ingredient Notes

• Olive Oil – Use any light, neutral-flavored oil. 
• Butter – Butter lends a rich and creamy flavor to the dish. You can use unsalted butter for better control over the salt content. If you want a dairy-free option, consider using a plant-based butter alternative like margarine.
• Garlic – Freshly minced garlic cloves impart a wonderful aromatic flavor. You can use garlic powder (about ¼ teaspoon) as a substitute.
• Minced Shallots – Shallots provide a mild onion flavor. If you don’t have shallots, you can substitute them with finely minced onions.
• Brussels Sprouts – Trim the ends of the Brussel sprouts and remove any brown leaves. For larger sprouts, halve or quarter them if necessary for even cooking. Fresh or frozen Brussels sprouts work well.
• Sea Salt – Sea salt enhances the overall flavor. You can use kosher salt or regular table salt if you don’t have sea salt.
• Black Pepper – Freshly ground black pepper adds a nice kick of flavor. Adjust the amount to your taste.
• Nutmeg – Nutmeg adds a warm and slightly sweet flavor. Grated whole nutmeg has the best flavor, but you can also use ground nutmeg.
• Double Cream – Double cream is a rich and heavy cream with a high fat content. If you can’t find double cream, you can use heavy cream or whipping cream as a substitute.
• White Cheddar – White cheddar cheese provides a sharp and tangy flavor. You can substitute it with other cheeses like Gruyère, Swiss, or Monterey Jack if you prefer different flavors.
• Parmesan Cheese – Freshly grated parmesan cheese adds a salty and savory depth of flavor. 
• Walnuts – Chopped walnuts add a delightful crunch and nutty flavor. You can substitute them with other nuts like pecans, almonds, or even pine nuts for a different texture.

How To Make Au Gratin Brussel Sprouts

Be sure to check out my guide on how to cook frozen brussel sprouts for even more tasty recipes and cooking tips. 

Get the complete ingredients list and instructions from the recipe card further below.

1. Preheat the oven to 375 degrees F / 190 degrees C and prepare the sprouts.
2. Heat an oven proof skillet over medium heat, then add the oil and butter. When the butter has melted, add garlic, onion, and brussel sprouts.
3. Season with salt and pepper and sauté for 10-12 minutes or until the sprouts are tender on the inside and crispy on the outside. 
4. In a small bowl, whisk the nutmeg into the cream. Remove the skillet from the heat and pour the cream over the Brussel sprouts.
5. Sprinkle cheddar and parmesan on top with half of the walnuts. Bake for 10 minutes until the cheese melts.
6. Remove and garnish with more walnuts, grated parmesan, and parsley.

Brussel Sprouts Gratin Pro Tips

• Trim the stem end of the Brussels sprouts and cut larger sprouts in half. Check for any discolored or damaged outer leaves and remove them. 
• Use an oven-proof pan or transfer to a baking dish.
• Whenever possible, grate your cheese fresh. Pre-packaged grated cheese often contains anti-caking agents, which can affect the texture of your gratin sauce.
• Pour the cream mixture evenly over the sprouts. There is no need to stir it before adding the cheese.
• Don’t be shy about the seasonings. The sea salt, black pepper, and nutmeg should be enough to elevate the flavors. Taste as you go and adjust to your liking.
• Add the chopped walnuts on top just before serving. 
• Bake until the top is golden brown and the Brussels sprouts are tender when pierced with a fork. Since we have precooked the sprouts, this step should only take about 5 minutes. 
• Allow the gratin to rest for a few minutes after removing it from the oven. This helps the flavors meld together and makes it easier to serve.
• You can prepare the gratin in advance and refrigerate it. When you’re ready to serve, simply bake it until heated through. This makes it a convenient dish for busy gatherings.
• Garnish with fresh thyme.

Delicious Variations 

• Add Meat – Stir in cooked bacon bits or shredded boiled chicken thighs or cubed ham for a robust flavor. 
• Add Veggies – Chopped onions, mushrooms or red peppers add flavor and color to the dish. 
• Add Heat – A pinch of cayenne pepper or red pepper flakes give this brussel sprouts casserole a spicy kick. 
• Add Breadcrumbs – Sprinkle with bread crumbs or crushed crackers for a crunchy topping.

Prep And Storage

• Prep Ahead – Make this in advance and refrigerate until ready to bake. Bake until warmed through and the cheese is melted and bubbly. 
• Store – Leftovers can be stored in an airtight container for up to 5 days. 
• Freeze – Because of the cream sauce, freezing this dish is not recommended.
• Reheat – Reheat in the oven until warmed through. You can also microwave. 

FAQs

Similar Recipes

• Smashed Brussel Sprouts.
• Crispy Air Fryer Brussel Sprouts.
• Instant Pot Brussels Sprouts.
• Scalloped Potatoes.
• Sweet Potato Gratin.

Serve Creamy Brussels Sprouts Gratin with:

• This Beef Tenderloin Air Fryer recipe is a perfect accompaniment.
• For a hearty and satisfying meal, pair with Smothered Pork Chops.
• Air Fryer Salmon Patties for a flavorful and low carb option.

Recommended Tools

• Sharp kitchen knives to make trimming and chopping a breeze.
• A great skillet for even cooking.
• The best sea salt flakes to expertly season your dish.
• For the best tools to help make your recipe even easier and more successful, check out my collection of the Best Kitchen Tools on Amazon.

Thank you for reading my Brussels sprouts gratin recipe post. And please come visit again as I continue to slice, dice and dream up affordable Air Fryer recipes, Instant Pot recipes, Southern recipes, and more. Thanks for supporting Recipes from a Pantry, food blog.

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