Thames River Fish Pie with Dill Cream

By AislePrompt Editorial · Published 2026-04-02 · Updated 2026-04-02

A creamy, comforting classic with flaky pastry and a rich dill-infused sauce featuring fresh mixed fish, evoking London's riverside dining traditions. This British-inspired one-pot recipe, ready in about 50 minutes, layers white fish fillets, butter, onion into a dessert worth slowing down for — great for weekend baking, holiday tables, or any time you want a sweet payoff at the end of a meal. Each serving lands at about 580 calories and feeds 4, so it slots into a weekend bake or a special-occasion dessert tray. Tap "Plan a meal with the AI" below to drop this recipe into your week and send the ingredients straight to Instacart. Nutrition values are approximate, calculated from USDA FoodData Central (fdc.nal.usda.gov) — verify against ingredient labels for any health-driven dietary plan.

Ingredients

• 1 lb (cod, haddock, and salmon, cut into 1-inch pieces) white fish fillets
• 2 tbsp butter
• 1 small, finely diced onion
• 2 cloves, minced garlic
• 1/4 cup all-purpose flour
• 2 cups milk
• 1/2 cup heavy cream
• 2 tbsp, chopped fresh dill
• 1/2 tsp salt
• 1/4 tsp black pepper
• 1/4 cup frozen peas
• 1 sheet (14 oz, thawed) puff pastry
• 1, beaten (for egg wash) egg

The pan we’d use for this → Best Nonstick Cookware for 2026: Top 5 Skillet Picks + Buying Guide

Instructions

1. Step 1: Preheat oven to 375°F (190°C). Melt 2 tbsp butter in a medium saucepan over medium heat, then add diced onion and sauté for 5 minutes until soft and translucent.
2. Step 2: Stir in minced garlic and cook for 1 minute until fragrant, then add flour and whisk continuously for 1 minute to form a roux.
3. Step 3: Gradually pour in 2 cups milk while whisking constantly, then add 1/2 cup heavy cream, 2 tbsp dill, 1/2 tsp salt, and 1/4 tsp black pepper. Cook for 5-7 minutes, stirring frequently, until sauce thickens and coats the back of a spoon.
4. Step 4: Add fish pieces and frozen peas to the sauce, stirring gently to combine. Transfer mixture to a 9x13-inch baking dish.
5. Step 5: Roll out puff pastry sheet to fit the dish top, place over filling, trim edges, and crimp. Brush with beaten egg.
6. Step 6: Bake for 25-30 minutes until pastry is golden brown and filling bubbles around the edges.