chef john's fisherman's pie

Ingredients

• Servings: 6
• for potato crust:
• 3 russet potatoes, peeled and cut into chunks
• 3 tablespoons butter
• 1 pinch freshly grated nutmeg
• salt and ground black pepper to taste
• 1 pinch cayenne pepper, or to taste
• 1/2 cup milk
• for the spinach:
• 2 teaspoons olive oil
• 12 ounces baby spinach leaves
• for the sauce:
• 3 tablespoons butter
• 3 tablespoons all-purpose flour
• 2 cloves garlic, minced
• 2 cups cold milk, divided
• 2 teaspoons lemon zest
• for the rest:
• 1 tablespoon butter
• salt and ground black pepper to taste
• 1 pinch cayenne pepper, or to taste
• 2 pounds boneless cod fillets
• 1/2 lemon, juiced
• 1 tablespoon chopped fresh chives for garnish

Recipe

Preparation Time: 15 mins Cook Time: 1 hr 10 mins

Ready Time: 1 hr 35 mins


• bring a large saucepan of salted water and to a boil; add russet potatoes to boiling water and cook until very tender, about 20 minutes. drain well. mash in 3 tablespoons butter until thoroughly combined. season with nutmeg, salt, black pepper, and cayenne pepper to taste. mash 1/2 cup milk into potato mixture until smooth.
• drizzle olive oil in a large dutch oven over medium-high heat, add spinach, and season with a big pinch of salt. cook, stirring occasionally, until spinach has wilted, about 1 minute. transfer to a bowl lined with paper towels to wick away excess moisture.
• heat 3 tablespoons butter and flour in a saucepan over medium heat; whisk mixture to a smooth paste. cook, stirring constantly, until mixture has a nutty smell and is slightly browned, about 2 minutes. add chopped garlic; whisk until fragrant, 10 to 20 seconds.
• whisk 1 cup cold milk into flour mixture; cook until thickened. whisk in remaining 1 cup milk and lemon zest. bring white sauce to a gentle simmer, whisking constantly; season with salt. turn heat to very low and keep sauce warm.
• preheat oven to 375 degrees f (190 degrees c). grease an 8x12-inch casserole dish with 1 tablespoon butter.
• season buttered pan with salt, black pepper, and cayenne pepper. lay boneless cod fillets into the pan in a single layer. season tops of fillets with more salt, black pepper, and cayenne pepper. spread spinach evenly over fish and drizzle with lemon juice. spoon white sauce over spinach; give casserole dish several taps and shakes to eliminate .
• drop mashed potatoes by heaping spoonfuls over the casserole and spread smoothly to cover. place dish a rimmed baking sheet to catch spills.
• bake in the preheated oven until bubbling, about 40 minutes. turn on oven's broiler and broil until potato crust has a golden brown top, about 2 minutes. fish should flake easily. let stand 10 minutes before serving. garnish with a sprinkle of chives.