Baked Halibut Tomato Basil

There's something about opening the oven to find a perfectly baked halibut gleaming under a crown of bright tomato relish that makes a Tuesday night feel like a celebration. I discovered this dish years ago when I wanted something that felt elegant but didn't demand hours of fussing, and it's become my go to whenever I need to impress without stress. The beauty of it is how the delicate fish stays so tender and moist, while that fresh relish on top adds this punchy, garden fresh brightness that reminds you why Mediterranean food works so well. It's become the recipe I reach for when I want to feel like I've accomplished something in the kitchen without it actually being complicated.

I made this for my sister one summer when she mentioned she was trying to eat lighter, and I watched her fork into it with this look of surprise that the food was both healthy and actually delicious. She went back for seconds and asked for the recipe, which is always the moment you know you've nailed something. Ever since then, it's been my favorite thing to pull out when someone says they're being good about what they eat but clearly doesn't want to eat sad chicken breast for the hundredth time.

Ingredients

• Halibut fillets: Look for thick, evenly sized pieces so they cook at the same rate—your fishmonger can help with this and it makes a real difference in how beautifully they turn out.
• Olive oil: Use regular olive oil for cooking the fish and save the expensive extra virgin stuff just for drizzling into the relish where you can actually taste its peppery richness.
• Sea salt and black pepper: These seem obvious but they're actually everything—don't skip seasoning the fish itself because that's where the flavor lives.
• Fresh lemon slices: These do double duty by flavoring the fish as it bakes and looking beautiful on the plate, which honestly matters.
• Cherry tomatoes: Quartering them by hand takes maybe two minutes and gives you these gorgeous little pieces that stay slightly intact in the relish instead of turning into mush.
• Fresh basil leaves: Add these at the very end, right before serving, so they stay bright green and don't turn dark and bruised.
• Red onion: Finely diced means it softens slightly in the relish and adds this gentle sharpness that balances the sweetness of the tomatoes.
• Garlic clove: Just one, minced fine—garlic has a way of taking over a party if you're not paying attention.
• Capers: These little briny pops are what make people ask what that delicious salty something is in the relish.
• Balsamic vinegar: A tablespoon is enough to bring everything together with a quiet acidity that makes the whole thing sing.

Instructions

Get your oven ready:

Preheat to 200°C (400°F) and line your baking sheet with parchment paper, which is honestly the best kitchen shortcut because it means zero cleanup and nothing sticks.

Prepare the halibut:

Pat the fillets completely dry with paper towels because moisture is the enemy of browning and you want that beautiful seared edge. Brush generously with olive oil and season both sides with salt and pepper—don't be shy.

Arrange and top:

Lay the fillets on your prepared sheet and place a few thin lemon slices on top of each one, which will flavor the fish as it cooks and infuse it with subtle brightness.

Bake:

Slide into the oven for 15 to 18 minutes until the fish is opaque and flakes easily with a fork—set a timer because three minutes either way changes everything.

Make the relish while you wait:

In a bowl, combine quartered tomatoes, basil, red onion, minced garlic, capers, extra virgin olive oil, and balsamic vinegar, then season with salt and pepper. Mix gently so you keep those tomato pieces intact and the whole thing doesn't turn into tomato jam.

Finish and serve:

Remove the halibut from the oven, transfer to plates, and top each fillet generously with the relish, letting some of those lovely juices pool on the plate.

Save

There was this moment, cooking this for my partner after a particularly long week, where I realized I wasn't stressed or watching the clock—I was just enjoying the smell of lemon and basil and knowing that something good was about to come out of the oven. That's when I understood why this became the recipe I always come back to, because it gives you back time instead of eating it.

Why This Fish Works So Well

Halibut is forgiving in a way that other fish isn't, which is why it's perfect for anyone who gets nervous about cooking seafood. The flesh is dense enough that it doesn't fall apart in the oven, but it's still delicate enough to be truly tender when you eat it. It also has a gentle flavor that doesn't overpower the relish—it's more like the two of them are having a conversation instead of competing for your attention.

The Magic of Fresh Basil

I used to add basil to the relish hours ahead of time, wondering why it always turned brown and bitter, until I finally figured out that basil is delicate and bruises easily when it sits around. Now I chop it right before serving, even if it feels a little last minute, and the difference is honestly remarkable. The whole relish suddenly tastes brighter and more alive, which sounds dramatic but it's true.

Serving Suggestions and Pairings

This is the kind of dish that stands beautifully on its own, but I've found that people love it even more when there's something else on the plate to balance it. Roasted potatoes soak up those relish juices in the best way, or you can go light and serve it with steamed green beans or a simple arugula salad. A crisp white wine like Sauvignon Blanc or Pinot Grigio is practically mandatory—something with enough acidity to match the brightness of the relish.

• If you want something heartier, roasted new potatoes or crusty bread are your friends for soaking up every last drop of those amazing juices.
• In the summer, serve this at room temperature with the relish on the side and it becomes a completely different but equally lovely dish.
• Don't skip plating this nicely because it looks as good as it tastes, and that visual element somehow makes it taste even better.

Save

This is the meal I make when I want to feel capable in the kitchen without sacrificing simplicity or flavor. It's proof that some of the best dinners are the ones that don't try too hard.

Recipe FAQs

→ What type of fish works best for this dish?

Halibut is ideal due to its firm texture and mild flavor, but cod or sea bass are excellent substitutes.

→ How do I know when the fish is done baking?

The halibut is ready when it becomes opaque and flakes easily with a fork, usually after 15-18 minutes at 200°C (400°F).

→ Can I prepare the tomato and basil relish ahead of time?

Yes, preparing the relish in advance helps flavors meld, but fresh preparation ensures the best texture and brightness.

→ What wine pairs well with this meal?

A crisp Sauvignon Blanc or a light Pinot Grigio complements the fresh flavors of the fish and relish nicely.

→ Are there any suggested variations for the relish?

Adding diced avocado can bring creaminess, and adjusting capers or garlic levels can tailor the relish to your taste.