
A sophisticated twist on the classic comfort dish, this French-inspired fish pie features a rich, velvety white wine sauce infused with aromatic fennel and leeks. Topped with elegant swirls of buttery mashed potatoes, it's a golden-baked masterpiece perfect for a cozy family dinner or entertaining guests.
Prepare the potatoes: Place the starchy potatoes in a large saucepan and cover with cold water. Bring to a boil, then reduce the heat and simmer for about 25 minutes until very soft. You can begin preparing the sauce while the potatoes cook.
Preheat the oven: Set your oven to 200°C (390°F) or 180°C for fan-assisted ovens. It is highly recommended to place a foil-lined baking tray on the bottom rack to catch any sauce that might bubble over during baking.
Season the fish: Pat the white fish fillets dry with paper towels to ensure a better texture. Cut them into bite-sized pieces and sprinkle all sides with salt. Set aside.
Sauté the aromatics: In a 26cm (10") cast-iron skillet or ovenproof pan, heat the olive oil and butter over medium-high heat. Add the onion, fennel, leek, and garlic. Sauté for 5 minutes, stirring regularly, until the vegetables are softened and lightly golden.
Make the sauce base: Sprinkle the flour over the sautéed vegetables and stir for 30 seconds. Pour in the white wine; it will simmer rapidly. Stir constantly until it forms a thick, pasty consistency.
Thicken the sauce: Slowly pour in the hot milk and heavy cream while whisking or stirring continuously. Season with salt and black pepper. Bring to a gentle simmer and cook for 1 minute until the sauce is thick enough to coat the back of a spoon.
Prepare the mashed potato topping: Drain the cooked potatoes well. Pass them through a potato ricer or return them to the pot and mash thoroughly with a manual masher (avoid using a blender, which makes them gluey). Stir in butter, salt, and white pepper, then gradually add hot milk until the mash is creamy but firm enough to hold its shape for piping.
Assemble the filling: Stir the fresh dill into the sauce. Gently nestle the fish pieces into the sauce so they are mostly submerged. Use a spatula to carefully coat them without breaking the pieces. Smooth the surface of the filling.
Add the topping: Transfer the mashed potatoes to a piping bag fitted with a star tip. Pipe mounds or swirls over the entire surface of the pie. Lightly spray the top with olive oil spray to help it brown.
Bake and serve: Bake for 35 minutes, rotating the pan halfway through, until the top is beautifully golden. If needed, place it under the grill (broiler) for a few minutes at the end. Let the pie rest for 10 minutes before serving to allow the sauce to thicken further.
For a more complex flavor, use a mix of white fish, salmon, and smoked haddock. Ensure your milk and cream are hot before adding them to the roux to prevent lumps. If you don't have a piping bag, you can spread the mash with a fork and create a textured pattern to achieve a similar crispy effect.




