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U.S. measurements first, metric equivalents in parentheses. Conversions are approximate; oz means weight ounces, not fluid ounces.
- 3 cod fillets, approx. 6 oz (170 g) each (total ~18 oz (510 g)) - 2 tbsp (30 g) unsalted butter (for cooking) - 2 tbsp (30 g) unsalted butter (for béchamel) - 2 tbsp (16 g) all-purpose flour - 1 1/2 cups (360 ml) whole milk - 1/2 cup (120 ml) fish stock or reserved poaching liquid - 1/2 tsp (2.5 g) Dijon mustard - 1/4 tsp (0.5 g) ground nutmeg - 1/2 tsp (2.5 g) salt, or to taste - 1/4 tsp (1.25 g) ground black pepper - 1/2 cup (50 g) grated Gruyère or aged cheddar - 1/3 cup (35 g) fresh breadcrumbs - 1 small shallot, finely chopped (about 2 tbsp (15 g)) - 1 tbsp (15 ml) chopped fresh parsley - 1 tbsp (15 ml) lemon juice - 1 tbsp (15 ml) olive oil (for breadcrumbs) - 1 tbsp (15 g) grated Parmesan (optional, for topping) - 1 tbsp (15 g) butter, to dot on top before baking
- 3 cod fillets, approx. 6 oz (170 g) each (total ~18 oz / 510 g) - 2 tbsp (30 g) unsalted butter (for cooking) - 2 tbsp (30 g) unsalted butter (for béchamel) - 2 tbsp (16 g) all-purpose flour - 1 1/2 cups (360 ml) whole milk - 1/2 cup (120 ml) fish stock or reserved poaching liquid - 1/2 tsp (2.5 g) Dijon mustard - 1/4 tsp (0.5 g) ground nutmeg - 1/2 tsp (2.5 g) salt, or to taste - 1/4 tsp (1.25 g) ground black pepper - 1/2 cup (50 g) grated Gruyère or aged cheddar - 1/3 cup (35 g) fresh breadcrumbs - 1 small shallot, finely chopped (about 2 tbsp / 15 g) - 1 tbsp (15 ml) chopped fresh parsley - 1 tbsp (15 ml) lemon juice - 1 tbsp (15 ml) olive oil (for breadcrumbs) - 1 tbsp (15 g) grated Parmesan (optional, for topping) - 1 tbsp (15 g) butter, to dot on top before baking
U.S. measurements first, metric equivalents in parentheses. Conversions are approximate.
1. Preheat oven to 400°F (200°C). Bring a shallow skillet of milk and fish stock to a gentle simmer; poach the cod fillets 3–5 minutes until just opaque (they will finish cooking in the oven). Remove cod with slotted spoon and set aside; reserve poaching liquid. 2. In a saucepan over medium heat, melt 2 tbsp (30 ml) butter for the béchamel. Add chopped shallot and cook 1–2 minutes until softened. Stir in flour and cook 1 minute to form a roux. 3. Gradually whisk in the warmed milk and 1/4 cup (60 ml) reserved poaching liquid or fish stock, whisking until smooth and thickened, about 3–5 minutes. Stir in Dijon mustard, nutmeg, salt, and pepper. Remove from heat and stir in half the grated Gruyère and the lemon juice. 4. Gently flake the poached cod into large pieces and fold into the béchamel, reserving a few nice pieces for the top if desired. Stir in chopped parsley. 5. Spoon the cod mixture into a buttered shallow gratin or baking dish (about 9x9 in / 23x23 cm). Mix breadcrumbs with olive oil and remaining Gruyère (and Parmesan if using); sprinkle evenly over the top. Dot with small pieces of remaining butter. 6. Bake in the preheated oven 15–20 minutes, until the top is golden and bubbling and the gratin is heated through. For extra browning, finish 1–2 minutes under the broiler—watch closely. 7. Let rest 5 minutes, then serve hot with lemon wedges and a simple green vegetable or boiled potatoes.
1. Preheat oven to 400°F (200°C). Bring a shallow skillet of milk and fish stock to a gentle simmer; poach the cod fillets 3–5 minutes until just opaque (they will finish cooking in the oven). Remove cod with slotted spoon and set aside; reserve poaching liquid. 2. In a saucepan over medium heat, melt 2 tbsp butter for the béchamel. Add chopped shallot and cook 1–2 minutes until softened. Stir in flour and cook 1 minute to form a roux. 3. Gradually whisk in the warmed milk and 1/4 cup (60 ml) reserved poaching liquid or fish stock, whisking until smooth and thickened, about 3–5 minutes. Stir in Dijon mustard, nutmeg, salt, and pepper. Remove from heat and stir in half the grated Gruyère and the lemon juice. 4. Gently flake the poached cod into large pieces and fold into the béchamel, reserving a few nice pieces for the top if desired. Stir in chopped parsley. 5. Spoon the cod mixture into a buttered shallow gratin or baking dish (about 9x9 in / 23x23 cm). Mix breadcrumbs with olive oil and remaining Gruyère (and Parmesan if using); sprinkle evenly over the top. Dot with small pieces of remaining butter. 6. Bake in the preheated oven 15–20 minutes, until the top is golden and bubbling and the gratin is heated through. For extra browning, finish 1–2 minutes under the broiler—watch closely. 7. Let rest 5 minutes, then serve hot with lemon wedges and a simple green vegetable or boiled potatoes.
Per serving | Servings: 4
Generated: 2026-11-05T19:38:21+00:00
*Values are estimates based on USDA data and mathematical calculations. Actual values may vary. Where data are unavailable, those contributions are excluded. Sodium is a known subtotal. Missing contributions are unknown, not zero.