Grilled Onion-Butter Cod

Grilled butter onion cod recipe

The Spruce / Julia Hartbeck

Prep: 10 mins
Cook: 15 mins
Total: 25 mins
Servings: 4 servings
Nutritional Guidelines (per serving)
308 Calories
16g Fat
1g Carbs
36g Protein
See Full Nutritional Guidelines Hide Full Nutritional Guidelines
Nutrition Facts
Servings: 4
Amount per serving
Calories 308
% Daily Value*
Total Fat 16g 21%
Saturated Fat 8g 39%
Cholesterol 126mg 42%
Sodium 676mg 29%
Total Carbohydrate 1g 0%
Dietary Fiber 0g 1%
Protein 36g
Calcium 28mg 2%
*The % Daily Value (DV) tells you how much a nutrient in a food serving contributes to a daily diet. 2,000 calories a day is used for general nutrition advice.
(Nutrition information is calculated using an ingredient database and should be considered an estimate.)

This deliciously grilled cod has a fantastic, buttery flavor and texture. The onion and white wine combine with the butter to create a sophisticated sauce that, although simple to make, will taste as if you spent hours making it. Served with your favorite grilled potatoes or vegetable of your choice, this dish makes the perfect weeknight meal or impressive entree for a special gathering. 


  • 1/4 cup butter
  • 1 small onion, finely chopped
  • 1/4 cup white wine
  • 4 (6-ounce) cod fillets
  • 1 tablespoon extra-virgin​ olive oil
  • 1/2 teaspoon salt (or more to taste)
  • 1/2 teaspoon freshly ground black pepper
  • For Serving: lemon wedges

Steps to Make It

  1. Gather the ingredients. Preheat grill to medium-high heat.

    Ingredients for grilled onion butter cod recipe
    The Spruce / Julia Hartbeck
  2. In small skillet, melt butter. Add onions and cook for 1 to 2 minutes.

    Melt butter
    The Spruce / Julia Hartbeck
  3. Add white wine and let simmer for an additional 3 minutes. Remove from heat and let cool for 5 minutes.

    Add white wine
    The Spruce / Julia Hartbeck
  4. Brush fish fillets with extra-virgin olive oil and sprinkle with salt and pepper. Place fish on a well-oiled grill rack, close lid, and cook for 8 minutes.

    Brush fish fillets
    The Spruce / Julia Hartbeck
  5. Baste cod with butter sauce and carefully flip over fish. Cook for an additional 6 to 7 minutes, basting fish a total of 2 to 3 times, or until fish is opaque, flakes easily with a fork, and reaches an internal temperature of 145 F.

    Baste cod
    The Spruce / Julia Hartbeck
  6. Remove cod from the grill, top with lemon wedges, and serve.

    Cod onion
    The Spruce / Julia Hartbeck


  • It is common to be nervous about cooking fish fillets on the grill. The fish can easily fall apart and slip through the grates or it can stick to the grill making it almost impossible to turn in one piece. It is important to grease the grill grates very well before cooking a piece of fish and to have a large grilling spatula on hand. You should only flip the fish once and leave it alone to cook the rest of the time.
  • It is always best to grill with your lid down, and remember every time you open that lid, you're releasing heat and potentially upping the cooking time.
  • There are other options however to cooking fish on the grill: use a grilling fish basket, grill on a wooden plank, or wrap the fish in a foil packet, making for easy clean up (the fish will have a smoky grilled flavor but not get any grill marks).
  • Store any leftover cooked fish in an airtight container in the refrigerator for up to 3 days after initial cooking. Flake any leftovers and add to soups or stews. 

Recipe Variations

  • Whether your fish counter is void of cod fillets, or you just aren't happy with how they look, there are other varieties of fish you can use in this recipe. Good substitutes for cod are mahi-mahi, grouper, striped bass, haddock, pollack, hake, and black cod.
  • Substitute onion for a shallot. You might need two shallots to equal the size of one onion.
  • For added brightness and flavor, add chopped fresh herbs to the butter. Try basil, tarragon, parsley, or dill.