Coastal Anglesey Egg with Smoked Haddock & Leeks

🌍 Cuisine: British
🏷️ Category: Main Course
⏱️ Prep: 25 minutes
🍳 Cook: 35 minutes
👥 Serves: 4 servings

📝 About This Recipe

Hailing from the rugged coastline of North Wales, this elevated version of the traditional Anglesey Egg (Wyau Ynys Môn) transforms humble ingredients into a luxurious seafood gratin. This dish features velvety mashed potatoes and tender leeks enriched with flakes of succulent smoked haddock, all blanketed in a rich, mustard-infused Mornay sauce. It is the ultimate British comfort food—a golden, bubbling masterpiece that perfectly balances smoky, salty, and creamy notes.

🥗 Ingredients

The Potato Base

  • 1 kg Maris Piper or King Edward potatoes (peeled and chopped into chunks)
  • 50 g Unsalted butter (at room temperature)
  • 4 tablespoons Whole milk (warm)
  • 2 pieces Large leeks (white and light green parts only, finely sliced)

The Fish and Eggs

  • 300 g Smoked Haddock fillet (undyed preferred)
  • 4-6 pieces Large eggs (hard-boiled for 8 minutes, peeled and halved)
  • 1 piece Bay leaf
  • 4-5 pieces Whole peppercorns

The Cheese Sauce and Topping

  • 40 g Unsalted butter
  • 40 g All-purpose flour
  • 500 ml Whole milk (use the poaching milk from the fish)
  • 150 g Mature Welsh Cheddar (grated)
  • 1 teaspoon English mustard
  • 1 tablespoon Fresh chives (finely chopped)
  • 3 tablespoons Panko breadcrumbs (for a crunchy topping)

👨‍🍳 Instructions

  1. 1

    Place the chopped potatoes in a large pot of salted water. Bring to a boil and simmer for 15-20 minutes until tender.

  2. 2

    While potatoes cook, place the smoked haddock in a wide skillet. Cover with the 500ml of milk, add the bay leaf and peppercorns. Simmer gently for 5-7 minutes until the fish flakes easily.

  3. 3

    Carefully remove the fish from the milk and set aside. Strain the poaching milk into a jug to reuse for the sauce—this is liquid gold!

  4. 4

    In a small frying pan, melt 20g of butter and sauté the sliced leeks over medium heat for 8-10 minutes until soft and sweet, but not browned.

  5. 5

    Drain the cooked potatoes and mash thoroughly with 30g of butter and 4 tablespoons of warm milk until smooth. Stir the softened leeks into the mash.

  6. 6

    Flake the poached haddock into large chunks, removing any stray bones or skin, and gently fold it into the leek and potato mixture.

  7. 7

    Preheat your oven to 200°C (400°F/Gas Mark 6). Grease a medium-sized ovenproof baking dish.

  8. 8

    To make the sauce, melt 40g of butter in a saucepan. Whisk in the flour and cook for 1-2 minutes to create a roux.

  9. 9

    Gradually whisk in the reserved poaching milk. Continue whisking over medium heat until the sauce thickens and becomes glossy.

  10. 10

    Remove the sauce from heat. Stir in 100g of the grated Cheddar, the English mustard, and the chopped chives until melted and combined.

  11. 11

    Spread the potato, leek, and fish mixture into the base of your prepared baking dish. Create small wells and nestle the halved hard-boiled eggs into the mash, yolk-side up.

  12. 12

    Pour the cheesy Mornay sauce evenly over the top, ensuring the eggs are partially covered.

  13. 13

    Mix the remaining 50g of cheese with the breadcrumbs and sprinkle over the top for texture.

  14. 14

    Bake for 15-20 minutes until the top is golden brown and the sauce is bubbling around the edges.

  15. 15

    Let it rest for 5 minutes before serving to allow the flavors to settle. Garnish with a few extra chives.

💡 Chef's Tips

Always use undyed smoked haddock for a cleaner, more natural flavor and appearance. Don't overcook the eggs in the initial boiling phase; 8 minutes ensures the yolks stay bright and don't develop a grey ring. If the sauce feels too thick, add a splash more milk; it should be pourable but coating. For an extra Welsh touch, use Caerphilly cheese instead of Cheddar for a saltier, tangier profile. Ensure the potatoes are mashed while hot to prevent a gluey texture.

🍽️ Serving Suggestions

Serve with a side of buttered garden peas or steamed samphire for a salty, oceanic crunch. A crisp, dry white wine like a Chenin Blanc or a light Welsh cider cuts through the richness beautifully. Accompanied by a simple green salad with a sharp lemon vinaigrette to balance the creamy sauce. Warm, crusty sourdough bread is essential for mopping up every last drop of the cheese sauce.