Save The smell of salmon roasting with caramelized onions stopped my neighbor mid-conversation through the kitchen window. She leaned in and asked what I was making, and I realized this dish had become my accidental signature—a one-pan wonder born from a night when I had fresh fish, wilted leeks in the crisper, and zero patience for complicated dinners. The parsley dressing came later, after a friend suggested I needed something bright to cut through the richness. Now it feels incomplete without it.
I made this for my sister the week she moved into her new apartment, back when her kitchen still smelled like paint and her cutting board was the only thing unpacked. We ate straight off the baking sheet with forks, lemon slices still warm and sticky on the salmon. She told me it tasted like something she would order out, and I promised her it was easier than it looked. That night became our tradition: one-pan dinners whenever one of us needed something comforting without the fuss.
Ingredients
- Salmon fillets (skin-on): The skin crisps beautifully against the hot pan and keeps the flesh moist, so leave it on and let it do its job.
- Leeks: Slice them into thick rounds so they hold their shape and get sweet and tender without falling apart in the oven.
- Red onion: Wedges work better than thin slices because they caramelize without burning, adding a slight sweetness that balances the fish.
- Olive oil (for roasting): A good drizzle helps everything brown evenly and prevents sticking, so do not skimp here.
- Sea salt and black pepper: Simple seasoning lets the vegetables and salmon shine without competing flavors.
- Lemon slices: They roast right on top of the salmon, infusing it with citrus and leaving behind sticky, sweet edges.
- Fresh flat-leaf parsley: The base of the dressing, it brings a grassy brightness that cuts through the richness of the fish.
- Garlic clove: Just one small clove minced fine adds sharpness without overwhelming the delicate parsley.
- Dijon mustard: It emulsifies the dressing and adds a subtle tang that ties everything together.
- Capers: Chopped small, they give little bursts of briny flavor that wake up each bite.
- Lemon zest and juice: Fresh citrus makes the dressing sing and balances the olive oil with acidity.
- Extra-virgin olive oil (for dressing): Use your best bottle here because the flavor really comes through in the finished drizzle.
Instructions
- Preheat and Prep:
- Set your oven to 400°F so it is fully heated when the vegetables go in. A hot oven is key to getting those edges golden and sweet.
- Prepare the Vegetables:
- Spread the leeks and red onion on a large baking sheet in a single layer, drizzle with olive oil, and season with salt and pepper. Toss everything with your hands to coat evenly, making sure each piece has a little oil to help it caramelize.
- Start Roasting:
- Slide the sheet into the oven and roast the vegetables for 10 minutes. This head start ensures they get tender and golden before the salmon goes in.
- Add the Salmon:
- Pull the sheet out and nestle the salmon fillets skin-side down among the vegetables, then lay lemon slices over the top. The vegetables will cradle the fish and keep it moist as it cooks.
- Finish Roasting:
- Return the pan to the oven and roast for 12 to 15 minutes, until the salmon is just cooked through and flakes easily. The vegetables should be soft and lightly charred at the edges.
- Make the Dressing:
- While everything roasts, combine parsley, garlic, Dijon, capers, lemon zest, olive oil, and lemon juice in a small bowl. Stir well and taste, adjusting salt and pepper as needed.
- Plate and Serve:
- Transfer the salmon and vegetables to plates, then spoon the parsley dressing generously over the top. Serve immediately while everything is warm and fragrant.
Save There was a rainy Tuesday when I served this to my partner after a long day, and he paused mid-bite to say it tasted like care. I laughed, but I knew what he meant—the kind of meal that feels generous without being complicated, nourishing without being heavy. It is become our go-to whenever we need something that feels like a reset, a plate that reminds us that good food does not have to be hard.
Choosing Your Salmon
Look for fillets that are firm to the touch and smell like the ocean, not fishy or sour. Skin-on pieces hold together better during roasting and give you that satisfying crispy edge if you sear them quickly in a hot pan before serving. I usually buy wild-caught when I can find it, but good-quality farmed salmon works beautifully here too. The key is freshness, so ask your fishmonger what came in that day and trust their guidance.
Working With Leeks
Leeks hide dirt between their layers, so I slice them first and then swish them around in a big bowl of cold water, letting the grit sink to the bottom. Pat them dry with a towel before tossing with oil, or they will steam instead of roast. They shrink a lot in the oven, so do not be shy about using two large ones—they become sweet and almost buttery when roasted properly. If you cannot find leeks, substitute with thinly sliced fennel or extra onions, though you will miss that delicate oniony sweetness.
Serving and Storing
This dish is best enjoyed fresh from the oven, but leftovers keep well in the fridge for up to two days in an airtight container. Reheat gently in a low oven or enjoy the salmon cold over greens with extra dressing drizzled on top. The parsley dressing stays vibrant for about three days and works beautifully on roasted chicken, grilled vegetables, or even tossed with pasta.
- Serve with roasted fingerling potatoes or crusty bread to soak up the dressing.
- Add a handful of cherry tomatoes to the baking sheet for extra color and sweetness.
- For a heartier meal, toss in some halved baby potatoes with the leeks at the start of roasting.
Save This recipe has taught me that simplicity and flavor are not opposites, they are partners. I hope it brings you the same easy comfort it has brought to my table, one golden, fragrant pan at a time.
Recipe FAQs
- → Can I use frozen salmon fillets for this dish?
Yes, just ensure the salmon is fully thawed and patted dry before roasting. This helps achieve better browning and prevents excess moisture on the pan.
- → What can I substitute for leeks?
You can use sliced fennel bulb or additional onions. Fennel adds a mild anise flavor that pairs beautifully with salmon, while more onions keep the dish simple and sweet.
- → How do I know when the salmon is perfectly cooked?
The salmon is done when it flakes easily with a fork and reaches an internal temperature of 145°F. It should appear opaque throughout with a slightly translucent center if you prefer it medium.
- → Can I make the parsley dressing ahead of time?
Absolutely. Prepare the dressing up to 24 hours in advance and store it covered in the refrigerator. Bring it to room temperature and stir well before serving for the best flavor.
- → What sides complement this salmon dish?
Roasted potatoes, steamed rice, quinoa, or crusty bread work wonderfully. A simple green salad or steamed asparagus also makes an excellent accompaniment to balance the richness of the salmon.
- → Can I use a different type of fish?
Yes, trout, cod, halibut, or sea bass all work well with this preparation. Adjust cooking time based on thickness—thinner fillets may need 10-12 minutes instead of 15.