FISH PIE

 

FISH PIE

The main ingredient in a fish pie—the fish—is typically pre-cooked (poached) on the stovetop before assembling the pie and baking it in the oven. This gentle cooking method ensures the fish stays tender and flaky without overcooking during the shorter bake time (usually 20–30 minutes at 180–200°C/350–400°F). Poaching also helps infuse flavor into the creamy sauce.

It's much better to poach the fish in milk rather than water. Milk adds richness, tenderness, and a subtle dairy flavor that enhances the overall dish, while also serving as the base for the white sauce (you'll thicken the poaching liquid with butter and flour afterward). Water would dilute the taste and result in a less luxurious pie. Here's a quick overview of the process based on standard recipes:

 

Step	Description	Why Milk Over Water?
Poach the Fish	Simmer skinless fish fillets (e.g., cod, haddock, or salmon; about 400–500g total) in 400–500ml milk with optional aromatics like onion, bay leaf, or peppercorns for 5–8 minutes until just opaque and flaky. Remove fish, then reserve the milk.	Milk tenderizes the fish and builds a flavorful sauce base; water lacks creaminess and doesn't infuse as well.
Assemble	Flake the poached fish into a dish with cooked veggies (e.g., leeks, peas), pour over the thickened milk sauce, top with mashed potatoes, and optionally cheese.	Pre-poaching prevents sogginess or dryness in the oven.
Bake	20–30 minutes until golden and bubbling.	Final bake is for crisping the topping, not fully cooking the fish.

 

If your recipe uses raw fish straight into the oven (rare for traditional pies), it can work but risks uneven cooking—pre-poaching is the reliable approach.