Here is one of my favorite haddock recipes! Flaky white haddock (or cod) is baked with sweet cherry tomatoes, melting fennel bulb, garlic, and fresh herbs. It’s a simple, healthy, one-pan fish dinner the family will love.
This healthy fish dinner happens on repeat on busy weeknights. Haddock, if unfamiliar, is a member of the cod family, a popular white fish from New England known for its flaky texture, sweet, clean flavor, and low oil content. It’s perfect for folks who don’t like “fishy” oily fish, like my husband.
It’s wonderfully flavorful with the melting fennel, roasted tomatoes, garlic, lemon, and fresh herbs. Sometimes we serve it simply, with some crusty bread to mop up the flavorful juices. But my favorite way to serve it is with creamy polenta, turning the whole thing into a cozy, rustic Italian meal. I love that it can be made in one skillet, and the oven does most of the work. I purposely left the breadcrumbs out of this recipe, keeping it light and lean.
Haddock Recipe Ingredients
- Haddock or Cod (other mild white fish options: halibut, sablefish, or sea bass), fresh and flaky, perfect for gentle baking.
- Fennel bulb, sliced paper-thin, lends a mild anise note that mellows beautifully in the oven.
- Cherry or grape tomatoes, juicy and vibrant, bursting as they roast to create a light, natural sauce.
- Extra Virgin Olive oil, used to lightly coat the fish and vegetables, adding richness and helping everything roast evenly.
- Garlic, finely minced, brings a savory depth that infuses the dish as it bakes. Or use garlic powder.
- Sweet onion, very thinly sliced so it softens and caramelizes as it roasts.
- Lemon zest, bright and aromatic, lifts the flavors of the fish and vegetables.
- Kosher salt, to season and enhance all the natural flavors.
- Cracked black pepper, for a subtle warmth and gentle bite.
- Fresh thyme, earthy and fragrant, woven throughout the dish. Feel free to use fresh parsley.
- Lemon juice, added for a fresh, clean acidity that balances the sweetness of the vegetables.
- Thyme sprigs, scattered over the top just before serving for a fresh, herbal finish.
How to make this Haddock Recipe
Step one: Preheat the oven to 400F, then cut the haddock filets into smaller portions.
Step two: Place the haddock fillets in a bowl and toss with marinade ingredients. Set aside. You could marinate overnight.
Step three: While the fish is marinating, begin layering the onion, thinly sliced fennel, and tomatoes in an oven-proof baking dish or braiser.
Step four: Drizzle with olive oil, lemon, salt and pepper and roast in the oven until the fennel is tender, about 30 minutes.
Step five: Nestle the fish into the veggies with the thyme, then place back in the oven for 7-9 minutes, or until the fish is cooked to your liking. When it comes out of the oven, squeeze with lemon and serve.
Storage
Leftover haddock will keep up to 3 days in an airtight container in the fridge. Reheat in a 350F oven or on the stove top.
What to serve with Baked Haddock
I love this dish on it’s own, or with creamy polenta. It’s also great with rice or a grain. Here are some ideas.
- Creamy Polenta - Smooth, buttery, and comforting, my favorite side that pairs perfectly with this dish!
- Black Rice – Nutty and slightly chewy, a beautiful dark rice that pairs perfectly with tender-baked haddock.
- Quinoa– Light, fluffy, and packed with protein; a healthy, quick-cooking side for fish.
- Roasted Garlic Mashed Potatoes- Creamy, rich, and full of roasted garlic flavor, perfect for soaking up any pan juices.
- Instant Pot Risotto - Rich, creamy, and effortlessly elegant with haddock.
Enjoy the Baked Haddock and please let us know how you like it in the comments below!
More Healthy Fish Dinners
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- Baked Cod with Asparagus, Lemon, Garlic & Thyme
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- Baked Salmon with Dill Sauce and Asparagus
- Citrus Baked Salmon with Fingerlings
Baked Haddock Recipe
- Prep Time: 10 mins
- Cook Time: 45 mins
- Total Time: 55 mins
- Yield: 4 1x
- Category: fish, Main, seafood
- Method: Baked
- Cuisine: Italian
Description
Easy baked haddock with roasted tomatoes, fennel, garlic, and thyme — a healthy, gluten-free one-pot fish dinner ready in an hour.
Ingredients
- 1 lb Haddock (or other white fish like cod, halibut, sable or bass)
- 1 1/2 tablespoon olive oil
- 3 cloves garlic-minced
- lemon zest from one lemon
- 1/2 teaspoon kosher salt
- 1/4 teaspoon cracked pepper
- 1 tablespoon thyme
- 1/2 of a sweet onion- thinly sliced
- pinch salt and pepper
- juice of one lemon
- 1 teaspoon olive oil
- 1 fennel bulb- very thinly sliced
- 1 1/2 lbs cherry, grape or baby heirloom tomatoes
- Garnish with Thyme Sprigs
Instructions
- Preheat oven to 400F
- Cut fish into 6-8 pieces. In a medium bowl, mix oil, garlic, salt, pepper, thyme and lemon zest. Toss with fish, set aside.
- In a lightly oiled baking dish, place onion slices on the bottom. Scatter sliced fennel over top. Drizzle with 1 teaspoon olive oil, lemon juice from ½ a lemon, and sprinkle with a generous 3 finger pinch of salt and pepper.Top with tomatoes.
- Place in the oven for 30-35 minutes, giving a good shake, halfway through. Place the white fish overtop, nestling among the tomatoes. Drizzle any left over marinade over the fish and tomatoes. Place back in the oven and cook 7-8 minutes or until fish cooks to desired done-ness.
- Remove from oven. Squeeze with remaining ½ lemon, scatter with thyme and serve.
Notes
Leftovers will keep up to 3 days in the fridge. Fish can be marinated overnight.
Nutrition
- Serving Size: 4 ounces
- Calories: 208
- Sugar: 8.7 g
- Sodium: 1020.2 mg
- Fat: 7.5 g
- Saturated Fat: 1.1 g
- Carbohydrates: 16.7 g
- Fiber: 4.1 g
- Protein: 21.1 g
- Cholesterol: 61.2 mg
I notice you have a lovely Staub pot in the picture.So do you bake this great dish with the lid on or off?
Bake with the lid off!
Unbelievable! It’s now one of my go to meals! Yummy!
Thanks Don- glad you like it!
Can this recipe be tweaked to make a sheet pan dinner with roasted tomatoes shallots/sweet onions and fennel and then having fish on top? So it’s less saucy for presentation?
Yes- I think so! I would roast the fennel a bit first, then add tomatoes and onions, then add the fish so it doesn’t overcook.
Thank you
Have cooked this a number of times and never fails to please
Aweomse Heather!
Do you use 1 tbsp of fresh thyme or dried thyme?
I used Fresh thyme here!
My cousin Lorri made this tonight she said it fabulous and f so he’s a great chef so I take her word! Can’t wait to make it!
Great to hear, and thanks!
Would mahi work in place of halibut?
I think that should be fine!
Just finished eating my try at this great recipe. My wife and I really enjoyed it. I did use a little more virgin olive oil than recommended, as that keeps it super moist. I also added some marinated sweet red peppers, as they complement the tomatoes. Served it with a side-dish of lemon and herb basmati rice.
Thanks for a great recipe and an enjoyable lunch.
Greetings from North Wales, UK.
Thanks Phil, glad you liked!
This was my first time trying a recipe from your site and it was absolutley DIVINE! My local farmers market had Haddock on sale, so i did a quick search and came across your recipe. I decided to give it a try following the recipe minus the fennel (daughter has a food allergy). I served this with roasted asparagus and wild rice. This will go into our meal rotation and it’s definatley an excellent meal with a wonderful presentation for serving to company. Thank you!
Glad you enjoyed this!
Easy . Plenty of time to clean up and put left over produce away. I did substitute talipia for the fish. Civered and cooked for only 6 minutes. Delicious.
Loved it! Plus it looked beautiful
Great recipe, used Halibut …. served over long grain wild rice it was delicious! Will def make again!
I ran short of grape tomatoes, should I use the 10oz I have or add a can of fire roasted diced tomatoes??
Just use what you have. 🙂
This is a fantastic dish! Healthy, easy, and tasty! The bed of onions and fennel and tomatoes was especially lovely. Definitely making this again!
Very flavorful (and healthy!) We made it on the stove, simmering in a large saucepan, and it came out great. Will definitely make again.
This recipe was fabulous and I know I will make it again and again! It couldn’t have been easier, the ingredients were inexpensive, and it is a dish worthy of company, in my opinion.
Great to hear!
Another fantastic recipe! I decided this week to expand my fish horizon and made this with Sea Bass. You never fail me!
Yay Judy!!! Thanks so much, and glad it turned out for you! 🙌
This recipe was absolutely delicious – I used haddock – very easy to scale down for one person. Next time will be scaling up to impress friends. Served with creamy mash and tender stem broccoli. Thank you.
Dumb question, should I defrost frozen fish before using in this recipe? 🙂
Yes! Defrost!
I do not cook to often but when I bought a fennel in the week for the first time and had a nice portion of Hake in the the fridge I found your recipe and prepared it as said less the garlic as allergic to it. It went well my wife was impressed , the fish was so moist and tender
A big thank you
Thanks Barry, Glad you liked!
Can I use catfish for this recipe?..
I haven’t tried it personally, but give it a try!
This is so excellent! A true keeper to be made again and again.
It is simple extremely tasteful and just makes fish taste good. It would be good for non fish lovers.
Great to hear and thanks for the rating Joyce!
Undeniably my favorite fish recipe. Always turns out. I forgot the vidalea onion and used regular. It was still fantastic
Definitely putting this into my regular rotation of recipes. Layers of flavors, yum!
Thanks Jesse!
Saw this recipe and went to the grocery store right away. Cooked this tonight and it’s my new favorite dish that I cook! I used cod filets and added jalapeños to the veggie mixture because I enjoy some heat. Also added slices of butter when I added the fish in to make it more keto friendly. Absolutely the best baked fish I’ve had! Thanks so much for sharing!
Im so glad you enjoyed it!