Poached Cod with Egg and Dill Sauce

Why You’ll Love This Recipe

• Classic Swedish comfort: tender poached cod with a silky, dill-fragrant chopped-egg sauce.
• Gentle cooking means succulent fish every time—no overcooking.
• Streamlined timing so the sauce, fish, potatoes, and peas all finish together.
• Weeknight-simple, dinner-party elegant.

Grocery List

• Produce: Small waxy potatoes, fresh dill, lemon, small yellow onion, peas (fresh or frozen)
• Dairy: Unsalted butter, whole milk, heavy cream, eggs
• Pantry: Cod fillets, all-purpose flour, kosher salt, fine sea salt, white pepper, Dijon mustard, sugar, bay leaf, whole white peppercorns

Full Ingredients

Poached Cod

• 4 skinless cod loin fillets, 180–220 g each (about 800 g total)
• 1.5 L water
• 2 tbsp (20 g) kosher salt
• 1 tsp granulated sugar
• 10 whole white peppercorns
• 1 bay leaf
• 1/2 lemon, sliced
• 1 small yellow onion, thickly sliced

Egg Sauce (Äggsås)

• 4 large eggs
• 3 tbsp (42 g) unsalted butter
• 3 tbsp (24 g) all-purpose flour
• 2 cups (480 ml) whole milk
• 1/3 cup (80 ml) heavy cream
• 1 tbsp fresh lemon juice
• 1 tsp Dijon mustard
• 1 tsp fine sea salt, plus more to taste
• 1/4 tsp ground white pepper
• Pinch freshly grated nutmeg (optional)
• 3 tbsp finely chopped fresh dill (plus extra for garnish)

Buttered Potatoes

• 900 g small waxy potatoes (new potatoes or Yukon gold), scrubbed
• 2 tbsp (28 g) unsalted butter
• Fine salt, to taste

Steamed Peas

• 2 cups (200 g) green peas (fresh or frozen)
• 1 tbsp (14 g) unsalted butter
• Pinch fine salt

To Serve

• Lemon wedges (optional)
• Extra chopped dill

Step-by-Step Instructions

Step 1: Boil and chop the eggs

Place the eggs in a small pot, cover with cold water by 2 cm, and bring to a full boil. Immediately cover, turn the heat down to low, and cook for 10 minutes. Drain and cool under cold running water or in an ice bath until completely cool. Peel and chop the eggs into small pieces; set aside.

Step 2: Start the potatoes

Place the scrubbed potatoes in a pot, cover with cold, lightly salted water, and bring to a boil. Reduce to a gentle simmer and cook until just tender when pierced, 12–15 minutes depending on size. Drain well and keep warm in the pot with the lid ajar. Just before serving, toss with 2 tbsp butter and a pinch of salt.

Step 3: Build the poaching liquid (court-bouillon)

In a wide pot large enough to hold the fish in a single layer, combine water, kosher salt, sugar, peppercorns, bay leaf, lemon slices, and onion. Bring to a simmer over medium heat and let it burble gently for 5 minutes to perfume the liquid. Reduce heat to maintain 80°C/175°F—hot but not boiling.

Step 4: Make the velvety sauce base

In a medium saucepan, melt 3 tbsp butter over medium heat. Whisk in the flour and cook, whisking, for 60 seconds to eliminate raw flour taste without browning. Gradually add the milk, whisking constantly to avoid lumps, then add the cream. Bring to a gentle simmer and cook 4–5 minutes until the sauce coats the back of a spoon. Season with lemon juice, Dijon, 1 tsp fine sea salt, white pepper, and a tiny pinch of nutmeg if using. Keep the heat very low.

Step 5: Poach the cod gently

Slip the cod fillets into the 80°C/175°F poaching liquid. Cook 8–10 minutes, depending on thickness, until the fish flakes easily and registers 52–54°C (125–130°F) at the center. Transfer to a warm plate lined with paper towel to drain briefly. Discard aromatics or save the liquid for another use.

Step 6: Finish the egg-and-dill sauce

Fold the chopped eggs and dill into the warm sauce. Do not boil once the eggs are added—keep it just below a simmer so it stays silky. Taste and adjust seasoning with more salt, white pepper, or lemon to balance richness.

Step 7: Steam peas, finish sides, and plate

Steam peas until bright and tender, 3–4 minutes (or microwave with a splash of water). Drain, then toss with 1 tbsp butter and a pinch of salt. Toss the hot potatoes with their butter and season to taste. Plate the cod, spoon on a generous blanket of äggsås, and add the buttered potatoes and peas alongside. Garnish with extra dill and lemon wedges if you like.

Pro Tips

• Use thick cod loins for best texture; thinner tail pieces cook too fast.
• Keep the poaching liquid below a simmer—bubbles will rough up the fish. A thermometer is your best friend here.
• Season the sauce with white pepper to keep the look pristine and the flavor gently peppery.
• Chop the eggs fairly chunky for a more luxurious texture in the sauce.
• Warm plates help keep the sauce glossy and the fish hot when serving.

Variations

• Gluten-free: Replace the flour with 2 tbsp cornstarch; whisk into cold milk, then add to melted butter and heat gently until thickened.
• Herb swap: Add chives or parsley alongside (or instead of) dill for a different green note.
• Lighter sauce: Skip the cream and add an extra 1/2 cup (120 ml) milk; finish with an extra squeeze of lemon.

Storage & Make-Ahead

Hard-boil the eggs up to 3 days ahead; store peeled in the fridge. The béchamel base (before adding eggs and dill) can be made 2 days ahead; cool, cover, and refrigerate. Rewarm gently and stir in chopped eggs and dill just before serving. Leftover cod and sauce keep up to 2 days refrigerated; reheat very gently (low heat or a warm water bath) to avoid overcooking the fish and splitting the sauce. Potatoes and peas reheat well but are best fresh. Freezing is not recommended for the sauce or cooked fish.

Nutrition (per serving)

Approx. 780–830 calories; Protein 55–60 g; Carbohydrates 60–70 g; Fat 35–40 g; Fiber 6–8 g; Sodium ~900–1,100 mg. Estimates will vary with exact butter, cream, and salt used.