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Roasted Fish

Roasted Fish with Leeks and Capers

This Roasted Fish recipe is a weeknight hero — light, flavorful, and effortlessly elegant. Flaky white fish is roasted over caramelized leeks and capers, then finished with a zesty mustard-herb vinaigrette. It’s fresh, bright, and ready in just 30 minutes — perfect for cozy dinners or impressing guests with minimal effort.
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Prep Time 10 minutes
Cook Time 20 minutes
Total Time 30 minutes
Servings: 4 servings
Course: Dinner, Main Course
Cuisine: American, Mediterranean
Calories: 310
Ingredients Method Notes

Ingredients
  

For the Roasted Base
  • 2 medium leeks, white and pale green parts only, thinly sliced and rinsed well (about 4–5 cups)
  • 2 tbsp capers, drained
  • 3 tbsp extra-virgin olive oil for roasting
  • Kosher salt and freshly ground black pepper to taste
For the Fish
  • 4 fillets white fish (such as cod, halibut, or haddock) (about 6 oz each, skinless)
  • 1 tbsp extra-virgin olive oil for drizzling
  • Salt and black pepper for seasoning fish
For the Vinaigrette
  • 3 tbsp extra-virgin olive oil
  • 1 tbsp shallot, minced
  • 1 tbsp red wine vinegar
  • 1 tbsp fresh parsley, finely chopped
  • 1 tsp whole-grain mustard

Method
 

  1. Step 1 — Preheat
    Preheat your oven to 400°F (200°C) and prepare a sheet pan.
  2. Step 2 — Clean the Leeks
    Place sliced leeks in a bowl of cold water and swish to remove grit. Drain and pat completely dry for better caramelization.
  3. Step 3 — Roast the Leeks & Capers
    Spread leeks and capers on the pan, drizzle with olive oil, and season with salt. Roast for 15 minutes, stirring halfway, until softened and lightly browned.
  4. Step 4 — Season & Add the Fish
    Pat fish dry, drizzle with oil, and season with salt and pepper. Move leeks aside to make room, place fish on the pan, and roast for 10–12 minutes, until fish flakes easily with a fork.
  5. Step 5 — Make the Vinaigrette
    In a small bowl, whisk together olive oil, shallot, red wine vinegar, parsley, mustard, salt, and pepper until emulsified.
  6. Step 6 — Serve
    Transfer fish and roasted leeks to a platter. Spoon vinaigrette over top and serve immediately, garnished with extra herbs if desired.

Notes

Use any firm, flaky white fish such as cod, halibut, or sea bass. Avoid overcooking — start checking at 10 minutes. For variation, add chili flakes or lemon zest to the vinaigrette. Swap leeks for onions or fennel if needed. Not freezer-friendly — best enjoyed fresh or stored for up to 2 days refrigerated.