Quick, balanced, and full of bright Mediterranean-style flavor, Baked Halibut with Brussels Sprouts and Quinoa makes weeknight seafood feel polished without adding extra fuss. You get tender fish, caramelized vegetables, and a hearty grain base in one complete dinner that tastes fresh, savory, and satisfying.
This is the kind of meal that works beautifully when you want something wholesome and dinner-party worthy, but still practical enough for a regular evening in your kitchen.
The flavor combination is especially appealing here. Mild halibut pairs naturally with roasted Brussels sprouts and fennel, while lemon, garlic, olives, and sun-dried tomatoes bring contrast, depth, and a little briny punch.
What makes it so reliable is the layout. Everything roasts together on one pan while the quinoa waits underneath as the soft, fluffy base that ties the whole plate together.
What You Need to Make This Baked Halibut with Brussels Sprouts and Quinoa
Halibut brings the delicate, flaky centerpiece of the meal. A thick fillet works best so it stays moist while the vegetables roast underneath.
Brussels sprouts add hearty texture and those browned, lightly crisp edges that make the dish feel more substantial.
Fennel softens as it cooks and gives the pan a subtle sweetness that balances the saltier ingredients.
Cooked quinoa creates a satisfying bed for the fish and vegetables. It also soaks up the buttery lemon juices from the pan very well.
Kalamata olives add a salty, briny note that gives the dish its Mediterranean-inspired character.
Sun-dried tomatoes bring concentrated savory flavor and a slight chew that contrasts nicely with the tender fish.
Garlic is used in two parts so some seasons the vegetables and the rest perfumes the halibut as it bakes.
Lemon juice keeps the final dish lively and fresh, which is especially important with richer elements like butter and olives.
Butter and olive oil work together for flavor and roasting. The butter helps the fish stay luscious, while the olive oil helps the vegetables caramelize.
Parsley is the finishing touch that adds color and a clean, fresh note right before serving.
Salt and black pepper are simple, but they matter here. Since the ingredient list is not overly complicated, proper seasoning helps every part of the plate taste complete.
Step-by-Step Baked Halibut with Brussels Sprouts and Quinoa
STEP 1: Heat your oven to 400°F and get a large baking sheet ready. If your quinoa is not cooked yet, start that first so it is warm and ready by the time the fish comes out.
STEP 2: In a large bowl, toss the halved Brussels sprouts, sliced fennel, chopped sun-dried tomatoes, and olives with olive oil, part of the minced garlic, and half of the salt and pepper. Make sure the vegetables are evenly coated so they roast instead of steaming.
STEP 3: Spread the vegetable mixture out in a single layer on the baking sheet. Try not to overcrowd the pan, because a little space around the vegetables helps them get those lightly caramelized edges.
STEP 4: Place the halibut directly over the vegetables. Spoon or drizzle over the melted butter, lemon juice, and the remaining olive oil, then scatter the rest of the garlic on top. Finish with the remaining salt and pepper so the fish is seasoned all the way through.
STEP 5: Bake until the halibut turns opaque and flakes easily with a fork, and the vegetables are tender with browned tips. Depending on thickness, this usually takes about 15 to 20 minutes. You are looking for fish that feels just cooked, not dry.
STEP 6: Let the pan rest for a couple of minutes after it comes out of the oven. Spoon quinoa onto each plate, top with the baked halibut and roasted vegetables, and finish with chopped parsley so the dish tastes fresh and looks vibrant.
Helpful Tips
- Keep the vegetables in one even layer so they roast properly. Crowding the pan can make them soften before they brown.
- Check the halibut at the earlier end of the cooking range if your fillet is on the thinner side. Fish can move from tender to overdone quickly.
- Serve with the pan juices. The lemony butter and roasted vegetable juices are part of what makes the quinoa so flavorful.
Can I make this ahead of time?
You can cook the quinoa in advance and prep the vegetables a few hours ahead, which makes assembly much faster. For the best texture, bake the halibut right before serving so it stays moist and flaky instead of drying out during reheating.
What can I use instead of halibut?
Cod, haddock, sea bass, or another firm white fish can work well here. Choose a fillet thick enough to roast gently over the vegetables, and start checking doneness early because thinner fish may finish a little faster than halibut.
How do I know when the halibut is done?
The fish should look opaque from edge to center and separate easily when you press it with a fork. If it still looks glossy and resistant in the middle, give it another minute or two, then check again.
Can I use frozen halibut?
Yes, but thaw it fully first and pat it dry well before baking. Extra moisture can dilute the lemon-butter topping and make the vegetables roast less efficiently, so a dry fillet will give you a better final texture.
Perfect Pairings
A simple cucumber salad works very well with this dish because it adds a cool, crisp contrast to the warm roasted vegetables and buttery fish.
Warm pita or rustic bread is another smart addition if you want something to catch the extra juices from the pan and make the meal feel a little more generous.
For a more dinner-party style plate, serve it with a small side of plain Greek-style yogurt mixed with lemon and herbs. It adds a creamy contrast without competing with the flavors already on the sheet pan.
How to Store & Reheat
Store leftovers in an airtight container in the refrigerator for up to 2 days. Keep the quinoa with the fish if that is easiest, though storing it separately can help both parts keep a better texture.
You can freeze the cooked quinoa for up to 1 month, but the fish and roasted vegetables are best enjoyed fresh or from the fridge rather than frozen, since halibut can dry out and Brussels sprouts can soften too much after thawing.
To reheat, place the fish and vegetables in a covered baking dish and warm them in a low oven until heated through. This is gentler than blasting them in a hot oven and helps protect the texture of the halibut. The quinoa can be reheated with a small splash of water so it stays soft and fluffy.
Baked Halibut with Brussels Sprouts and Quinoa
Ingredients
For the quinoa:
- 2 cups cooked quinoa prepared according to the package instructions
For the halibut and vegetables:
- 1/4 cup Kalamata olives pitted and cut in half
- 1 fennel bulb thinly sliced
- 1 pound halibut fillet preferably wild-caught
- 2 tablespoons fresh Italian parsley chopped
- 1 teaspoon olive oil
- 1/4 cup oil-packed sun-dried tomatoes drained and chopped
- 1/2 teaspoon salt divided
- 2 tablespoons unsalted butter melted and cooled slightly
- 1 pound Brussels sprouts trimmed and halved
- 3 tablespoons freshly squeezed lemon juice
- 4 garlic cloves minced, divided
- 1 tablespoon olive oil
- 1/2 teaspoon black pepper divided
Instructions
- Preheat the oven to 400°F (200°C).
- In a large bowl, combine the Brussels sprouts, sliced fennel, sun-dried tomatoes, olives, 1 tablespoon olive oil, 1 minced garlic clove, 1/4 teaspoon salt, and 1/4 teaspoon black pepper. Toss thoroughly so the vegetables are evenly coated.
- Spread the vegetable mixture across a baking sheet in a single, even layer.
- Set the halibut on top of the prepared vegetables. Drizzle the fish with the melted butter, lemon juice, and the remaining 1 teaspoon olive oil. Scatter the remaining 3 minced garlic cloves over the halibut, then season with the remaining 1/4 teaspoon salt and 1/4 teaspoon black pepper.
- Bake for 15 to 20 minutes, or until the halibut is fully cooked and flakes easily with a fork and the vegetables are tender with lightly caramelized edges.
- While the fish and vegetables are in the oven, prepare the quinoa if it is not already cooked.
- Remove the baking sheet from the oven and allow the dish to rest briefly for a few minutes.
- To serve, spoon the cooked quinoa onto plates, then top with the baked halibut and roasted vegetables. Finish with the chopped parsley for a fresh garnish.
