Brussels Sprouts Gratin With Caramelized Shallots

The first time I encountered Brussels sprouts gratin, it was at a holiday potluck. I remember being immediately drawn to the dish – the bubbling, golden-brown topping hinted at something comforting and delicious. What truly sold me was the aroma: a symphony of sweet caramelized onions, nutty cheese, and that distinctive, earthy scent of Brussels sprouts, all melded together in perfect harmony. It turned out to be the surprise hit of the night, and I’ve been hooked ever since, tinkering with recipes to recreate that magic in my own kitchen.

Recipe Overview

• Prep Time: 30 minutes
• Cook Time: 50 minutes
• Total Time: 1 hour 20 minutes
• Servings: 8
• Dietary Type: Vegetarian

Ingredients

CARAMELIZED SHALLOTS

• 3 tablespoons butter
• 1 lb fresh shallots, peeled (of similar size; otherwise, cut to make similar size)
• ¾ – 1 ½ tablespoons sugar (depending on desired sweetness)
• 1 ½ tablespoons red wine vinegar or 1 ½ tablespoons balsamic vinegar
• ¼ teaspoon kosher salt
• ⅛ teaspoon fresh ground black pepper

TOPPING

• 3 cups coarse fresh breadcrumbs
• 3 tablespoons unsalted butter, melted
• 1 ½ teaspoons lemon zest (½ Tbsp.)
• ½ teaspoon kosher salt
• ½ teaspoon fresh ground black pepper
• 2 tablespoons fresh flat-leaf parsley, minced

GRATIN

• 1 tablespoon unsalted butter (to grease a 12-inch ovenproof nonstick fry pan)
• 2 lbs Brussels sprouts, trimmed and halved lengthwise
• Kosher salt (as if boiling pasta)
• Ice water (to halt cooking of Brussels sprouts)
• 2 tablespoons all-purpose flour
• 8 ounces Gruyere cheese, grated
• ½ ounce Parmigiano-Reggiano cheese, grated
• 1 teaspoon lemon zest
• 2 teaspoons kosher salt
• ¾ teaspoon fresh ground black pepper
• 1 cup heavy cream

Equipment Needed

• 12-inch ovenproof skillet
• Large pot
• Large bowl
• Small bowl
• Measuring cups and spoons
• Cheese grater
• Knife
• Cutting board
• Paper towels

Instructions

1. Preheat your oven to 400 degrees F (200 degrees C).

2. Begin preparing the caramelized shallots: In a 12-inch ovenproof skillet, melt 3 tablespoons of butter over medium heat.

3. Add the 1 lb of peeled shallots and ¾ to 1 ½ tablespoons of sugar (adjust the sugar amount based on your preference for sweetness), tossing to coat the shallots evenly.

4. Cook the shallots over medium heat for approximately 10 minutes, stirring occasionally. Continue cooking until the shallots begin to brown, developing a rich, golden color.

5. Add 1 ½ tablespoons of red wine vinegar (or balsamic vinegar for a slightly different flavor profile), ¼ teaspoon of kosher salt, and ⅛ teaspoon of freshly ground black pepper. Toss well to combine the vinegar and seasonings with the caramelized shallots.

6. Place the skillet containing the shallots in the preheated oven. Roast for 15-30 minutes, depending on the size of the shallots. Check for tenderness; it’s best if all the shallots are roughly the same size, ensuring they cook uniformly. They should be soft and deeply caramelized.

7. If preparing the shallots in advance, refrigerate them for up to 2 days. Before incorporating them into the Brussels sprouts gratin, allow them to come to room temperature.

8. Prepare the breadcrumb topping: In a bowl, combine 3 cups of coarse fresh breadcrumbs, 3 tablespoons of melted unsalted butter, 1 ½ teaspoons of lemon zest, ½ teaspoon of kosher salt, ½ teaspoon of freshly ground black pepper, and 2 tablespoons of minced fresh flat-leaf parsley.

9. Stir all the ingredients together until the breadcrumbs are evenly coated with the butter and seasonings. Set the breadcrumb topping aside until Step 16.

10. Preheat the oven to 375 degrees F (190 degrees C).

11. Grease a 12-inch ovenproof nonstick fry pan with 1 tablespoon of butter. Ensure the caramelized shallots are at room temperature.

12. Bring a large pot of water to a rapid boil over high heat. Add 2 lbs of trimmed and halved Brussels sprouts. Cook the Brussels sprouts until they are tender, approximately 5-7 minutes.

13. Drain the Brussels sprouts thoroughly and immediately transfer them to a bowl filled with ice water to halt the cooking process and preserve their vibrant green color.

14. Drain the Brussels sprouts from the ice water and pat them dry with paper towels to remove excess moisture. This step is crucial for preventing a soggy gratin.

15. In a separate bowl, combine 2 tablespoons of all-purpose flour, 8 ounces of grated Gruyere cheese, ½ ounce of grated Parmigiano-Reggiano cheese, 1 teaspoon of lemon zest, 2 teaspoons of kosher salt, and ¾ teaspoon of freshly ground black pepper.

16. Add 1 cup of heavy cream to the flour-cheese mixture. Stir until well combined. Then, gently fold in the drained and dried Brussels sprouts and the room-temperature caramelized shallots. Ensure the sprouts and shallots are evenly distributed throughout the creamy cheese mixture.

17. Transfer the Brussels sprouts mixture to the prepared fry pan, spreading it evenly to create a smooth top surface.

18. Sprinkle the breadcrumb topping mixture evenly over the Brussels sprouts and cheese mixture. Make sure to cover the entire surface for a consistent and appealing crust.

19. Bake in the preheated oven for approximately 35 minutes, or until the breadcrumbs are golden brown and the gratin is bubbling around the edges.

20. Remove the gratin from the oven and let it rest for 15 minutes before serving. This allows the gratin to set slightly and the flavors to meld together.

Expert Tips & Tricks

• Shallot Sweetness: Taste the caramelized shallots before adding them to the gratin. If they aren’t sweet enough for your liking, add a touch more sugar during the caramelization process.

• Brussels Sprout Bitterness: To minimize any potential bitterness in the Brussels sprouts, blanch them properly in boiling water and immediately shock them in ice water. Ensure they are thoroughly dried before adding them to the gratin.

• Cheese Selection: Gruyere is a classic choice for gratins, offering a nutty and slightly sweet flavor. However, you can experiment with other cheeses like Comté or Emmental for a different flavor profile.

• Make-Ahead Tip: The entire gratin can be assembled ahead of time, covered tightly, and refrigerated for up to 24 hours before baking. Add an extra 5-10 minutes to the baking time if baking from cold.

Serving & Storage Suggestions

Serve the Brussels sprouts gratin warm, directly from the ovenproof skillet or transferred to a serving dish. It makes an excellent side dish for roasted meats, poultry, or vegetarian mains.

Leftovers can be stored in an airtight container in the refrigerator for up to 3 days. To reheat, cover the gratin with foil and bake in a preheated oven at 350 degrees F (175 degrees C) until heated through, about 15-20 minutes. You can also microwave individual portions for quicker reheating.

Nutritional Information

Nutrient	Amount per Serving	% Daily Value
Calories	571.7 kcal	N/A
Calories from Fat	302 g	53%
Total Fat	33.6 g	51%
Saturated Fat	19.5 g	97%
Cholesterol	100 mg	33%
Sodium	1303.2 mg	54%
Total Carbohydrate	50.8 g	16%
Dietary Fiber	5 g	20%
Sugars	5.9 g	N/A
Protein	19.9 g	39%

Note: Nutritional information is an estimate and may vary based on specific ingredients and portion sizes.

Variations & Substitutions

• Gluten-Free: Use gluten-free breadcrumbs for the topping. You may also need to substitute the all-purpose flour with a gluten-free blend, though the small quantity used may not significantly impact gluten-sensitivity.
• Dairy-Free: While Gruyere and Parmigiano-Reggiano provide a distinctive flavor, you can try using dairy-free cheese alternatives, though the texture and flavor will change. For the heavy cream, substitute with cashew cream or a thick coconut cream.
• Vegetables: Add other roasted vegetables like butternut squash or sweet potatoes for a sweeter and more colorful gratin.
• Herbs: Experiment with different herbs in the breadcrumb topping, such as thyme or rosemary, for a more aromatic dish.
• Spice: Add a pinch of red pepper flakes to the Brussels sprouts mixture for a subtle kick.

FAQs (Frequently Asked Questions)

Q: Can I use frozen Brussels sprouts?
A: While fresh Brussels sprouts are preferred for their texture, you can use frozen Brussels sprouts. Be sure to thaw them completely and squeeze out any excess moisture before adding them to the gratin.

Q: Can I make this ahead of time?
A: Yes! The entire gratin can be assembled, covered, and refrigerated up to 24 hours before baking. Add a few extra minutes to the baking time if baking from cold.

Q: What if I don’t have an ovenproof skillet?
A: If you don’t have an ovenproof skillet, you can transfer the Brussels sprouts mixture to a greased baking dish before topping with breadcrumbs and baking.

Q: Can I use pre-made caramelized onions instead of shallots?
A: While shallots offer a more delicate flavor, you can substitute with caramelized onions in a pinch. The flavor profile will be slightly different.

Q: How do I prevent the breadcrumb topping from burning?
A: If the breadcrumb topping starts to brown too quickly, tent the gratin loosely with foil during the last 10-15 minutes of baking.

Final Thoughts

I hope you’ll give this Brussels Sprouts Gratin with Caramelized Shallots a try. It’s a fantastic way to transform simple ingredients into a dish that’s both comforting and elegant. Feel free to experiment with variations and make it your own. Don’t be shy about sharing your creations and feedback – happy cooking!