Brussels Sprouts Gratin

I first discovered this recipe during a cooking class in Brussels, ironically enough. The instructor explained that while Brussels sprouts have gotten a bad reputation, it's usually because they've been overcooked or underseasoned. This gratin changed my entire perspective. The key is halving the sprouts so they cook evenly and get that beautiful caramelization on the cut sides. When you blanch them first, then bake them in that garlicky cream sauce, magic happens. The cream reduces and intensifies, coating each sprout in silky richness. Then there's the cheese – a combination of nutty Gruyere and sharp Parmesan creates this incredible golden crust that shatters when you dig in your spoon. What I love most is how the Brussels sprouts retain a slight bite even after baking, providing textural contrast to the creamy sauce. It's comfort food that doesn't feel heavy, and it looks stunning enough to serve at your fanciest dinner party.

Why I love this recipe

This recipe holds a special place in my heart because it proves that simple ingredients, when treated with care, can create something extraordinary. I love how approachable it is – there's no complicated technique or hard-to-find ingredients, yet the result tastes like something from a fancy restaurant. The make-ahead nature is a lifesaver during busy holiday seasons; I can assemble it in the morning and just bake it before dinner. But beyond the convenience, I love how this dish brings people together. I've served it at countless gatherings, and it never fails to spark conversation. Even self-proclaimed Brussels sprouts haters find themselves going back for more, and there's something deeply satisfying about changing someone's mind about a vegetable they thought they disliked. The golden, bubbly cheese, the aromatic garlic and thyme, the tender-crisp sprouts – every element works in harmony to create pure comfort on a plate.

What You Need From Your Kitchen

• Brussels Sprouts: Trim the ends and remove any damaged outer leaves, then halve lengthwise for even cooking
• Heavy Cream: Brings richness and creates the luxurious sauce that coats every sprout
• Gruyere Cheese: Grate fresh for the best melting quality and nutty flavor throughout the dish
• Parmesan Cheese: Adds sharp, salty notes and helps create that irresistible golden crust
• Garlic: Mince finely and sauté gently to infuse the cream with aromatic flavor
• Fresh Thyme: Strip leaves from stems and add to the cream for an earthy, herbaceous note

Let's Make These Together

Blanch the Brussels Sprouts

Start by bringing a large pot of generously salted water to a rolling boil. While waiting, trim the stem ends of your Brussels sprouts and remove any yellowed or damaged outer leaves. Cut each sprout in half lengthwise through the core. Once the water is boiling, add the halved sprouts and blanch for 4-5 minutes. They should be slightly tender but still have a bite and maintain their vibrant green color. Drain immediately in a colander and spread them out on a clean kitchen towel to dry thoroughly. This step is crucial for removing any bitterness and ensuring they cook properly in the oven.

Create the Garlic Cream Base

In a large skillet over medium heat, melt the butter until it's foaming but not browning. Add your minced garlic and stir constantly for about 1-2 minutes until it becomes fragrant and just barely starts to turn golden. Be careful not to let it burn or it will taste bitter. Pour in the heavy cream and add the fresh thyme leaves. Bring the mixture to a gentle simmer, stirring occasionally. Let it cook for 3-4 minutes until the cream reduces slightly and coats the back of a spoon. Season generously with salt, freshly ground black pepper, and if you like, a tiny pinch of nutmeg for warmth and depth.

Assemble the Gratin

Butter your 9x13 inch baking dish generously to prevent sticking. Arrange the blanched and dried Brussels sprouts in the dish in a single layer, placing them cut-side up as much as possible. This positioning allows the cut surfaces to caramelize beautifully in the oven. Pour the warm garlic cream sauce evenly over all the sprouts, making sure each one gets coated. Give the dish a gentle shake to help the cream settle around all the sprouts. Sprinkle half of the grated Gruyere cheese over the top, distributing it evenly.

Add the Cheese Crust

In a small bowl, combine the remaining Gruyere with all of the Parmesan cheese. This two-cheese combination creates the perfect balance of meltability and flavor. Generously sprinkle this cheese mixture over the entire surface of the gratin, making sure to cover all the sprouts. For extra richness and to encourage browning, cut a tablespoon of butter into small pieces and dot them across the top of the cheese layer.

Bake and Serve

Place the dish in your preheated 400°F oven on the middle rack. Bake for 30-35 minutes, checking occasionally. The gratin is done when the cheese is deeply golden brown and bubbling vigorously, and when you can easily pierce the Brussels sprouts with a fork. If you notice the top browning too quickly before the sprouts are tender, loosely tent the dish with aluminum foil. For an extra-crispy, caramelized top, switch to the broiler for the final 2-3 minutes, but watch it like a hawk to prevent burning. Remove from the oven and let the gratin rest for 5 minutes before serving. This resting time allows the sauce to thicken slightly and makes serving much easier. Garnish with a few fresh thyme leaves if desired and serve hot.

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Switch Things Up

I remember the first time I made this gratin for Thanksgiving – I was nervous because half my family claimed they hated Brussels sprouts. I watched anxiously as everyone took their first bites, and the room went quiet. Then came the requests for seconds, then thirds! My uncle, who'd been the loudest Brussels sprouts critic, asked for the recipe before dessert was even served. Now it's become our family's most requested holiday side dish. I've learned that the secret is in the caramelization – those crispy, golden edges on the sprouts combined with the creamy sauce create an addictive contrast. Sometimes I add a pinch of nutmeg to the cream sauce for extra warmth, or swap Gruyere for a sharp white cheddar when I want a bolder flavor. The beauty of this dish is its versatility – it works alongside a formal roast or a casual weeknight chicken dinner.

Perfect Pairings

This gratin pairs beautifully with roasted meats, especially herb-crusted prime rib, garlic butter turkey, or rosemary lamb chops. The rich, creamy nature of the dish complements simple roasted proteins without competing for attention. For a complete vegetarian meal, serve it alongside wild rice pilaf and a crisp arugula salad with lemon vinaigrette. The gratin also works wonderfully as part of a holiday spread with cranberry sauce, mashed potatoes, and dinner rolls. Wine-wise, reach for a buttery Chardonnay or a light Pinot Noir that can stand up to the cream and cheese without overwhelming the Brussels sprouts.

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Frequently Asked Questions

→ Can I make this gratin ahead of time?

Absolutely! This is one of the best make-ahead side dishes. Assemble the entire gratin up to 24 hours in advance, cover tightly with plastic wrap or foil, and refrigerate. When you're ready to bake, remove it from the fridge while the oven preheats to take the chill off, then bake as directed, adding about 10 extra minutes to the cooking time since it's starting cold. The flavors actually meld beautifully overnight.

→ Why do I need to blanch the Brussels sprouts first?

Blanching serves multiple purposes: it removes some of the natural bitterness found in Brussels sprouts, it jump-starts the cooking process so they become perfectly tender during baking, and it helps them retain their vibrant green color. Without blanching, the sprouts might end up too firm or unevenly cooked in the time it takes for the cream sauce to reduce and the cheese to brown.

→ Can I use different types of cheese?

Yes, you can experiment with different cheeses! Gruyere and Parmesan are classic because Gruyere melts beautifully and has a nutty flavor, while Parmesan adds sharp, salty notes and helps create the golden crust. However, you could substitute white cheddar for a sharper flavor, Fontina for extra creaminess, or even Gouda for a smokier taste. Just make sure to use at least some hard cheese (like Parmesan) for that crispy top layer.

→ My gratin turned out watery. What went wrong?

Excess moisture is usually the culprit. Make sure you thoroughly dry the Brussels sprouts after blanching – pat them with paper towels or let them air dry for a few minutes. Also, don't skip simmering and reducing the cream sauce before adding it to the dish. If you're using frozen Brussels sprouts, this is even more critical as they release additional water during cooking. Finally, avoid covering the dish while baking, as this traps steam and prevents proper evaporation.

→ Can I make this recipe dairy-free or lighter?

For a lighter version, you can substitute half the heavy cream with whole milk or half-and-half, though the sauce won't be quite as rich and luxurious. For dairy-free, use full-fat coconut cream (the thick part from a chilled can) and nutritional yeast or dairy-free cheese alternatives, though the flavor and texture will be noticeably different. The traditional version is meant to be indulgent, so if you're watching calories, consider serving smaller portions alongside lighter dishes.

→ How do I prevent the cheese from burning?

Position your baking dish on the middle rack of the oven, not too close to the top heating element. If you notice the cheese browning too quickly (usually after about 20 minutes), loosely tent the dish with aluminum foil for the remaining cooking time. The foil will protect the top while allowing the Brussels sprouts underneath to continue cooking. Only use the broiler at the very end if you want extra browning, and stay nearby to watch it carefully – cheese can go from perfectly golden to burnt in less than a minute under the broiler.

Conclusion

This Cheesy Brussels Sprouts Gratin is proof that vegetables can be the star of any meal. The combination of tender Brussels sprouts with that luxurious cream sauce and golden cheese topping creates layers of flavor and texture that are simply irresistible. It's elegant enough for holiday dinners yet simple enough for weeknight meals. Whether you're feeding Brussels sprouts lovers or skeptics, this dish has the power to win everyone over with its perfect balance of creamy, cheesy, and caramelized goodness.