French Mustard-Herb Baked Salmon with Leeks & New Potatoes
Salmon fillets under a Dijon-herb glaze, roasted over softened leeks and new potatoes — a whole bistro dinner on one tray.
Best for heart health · omega-3 tray-bake dinner
This leans on the classic French pairing of mustard, leeks and salmon, but keeps it light: the leeks sweat down in a little oil until silky instead of buttery, and a thin Dijon-and-herb glaze on the fish crisps just enough in the oven to hold the fillets juicy. New potatoes roast alongside so it's genuinely one tray, start to finish. The omega-3-rich salmon and a bright squeeze of lemon make it feel special enough for a Friday but easy enough for a Tuesday.
Ingredients
- 600 g new potatoes , halved (quartered if large)
- 2 piece leeks , white and pale green, halved and sliced
- 30 ml olive oil
- 4 piece skin-on salmon fillets , about 140 g each
- 4 g fine sea salt
- 1 g black pepper , freshly ground
Glaze
- 30 g Dijon mustard
- 15 g wholegrain mustard
- 10 g Fresh dill , chopped
- 10 g fresh parsley , chopped
- 1 clove garlic cloves , grated
- 1 piece lemon , half zested and juiced, half in wedges
Instructions
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1
Heat the oven to 210°C (410°F). Toss the halved potatoes with half the olive oil, half the salt and a grind of pepper on a large sheet-pan and spread them out. Roast for 15 minutes to give them a head start.
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2
Meanwhile, soften the leeks: warm the remaining olive oil in a skillet over medium heat and cook the sliced leeks with a pinch of salt, stirring, until silky and sweet but not browned, 6–8 minutes.
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3
Whisk the glaze together — both mustards, dill, parsley, grated garlic, lemon zest and juice, and a grind of pepper.
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4
Pull out the pan, scatter the softened leeks among the potatoes, and clear a space for each fillet. Pat the salmon dry, set it skin-side down on the tray, season lightly, and spoon the mustard-herb glaze thickly over each fillet.
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5
Return to the oven and roast until the salmon flakes at the thickest point and reads 52–54°C for a just-cooked centre, 12–14 minutes, and the potatoes are tender and golden.
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6
Rest 2 minutes, then serve with lemon wedges and any pan juices spooned over.