If the cod has skin, it must be removed.

Sprinkle the fish with coarse salt.

Let the fish rest with the salt for 10 minutes on the kitchen counter. Meanwhile, prepare the sauce for steaming.

Put a pot on with butter and water. Bring it to a boil while preparing the green asparagus (they should be snapped, and the part that breaks off should be discarded). When the cod is placed in the cream sauce, put the green asparagus in the pot with butter and water. They are cooked over medium heat for about 10 minutes. Continuously check the asparagus; they should start to soften on the outside but still be firm inside. Let the asparagus drain on a tea towel.

In a tall pan, melt butter. Split a spring onion lengthwise and finely chop the shallots. Sauté the onions until soft without browning. Then add white wine and thyme. Let it simmer before adding cream and lemon zest, and bring it to just below boiling.

Rinse the cod under cold water to remove the salt and pat the fish dry with a clean tea towel or paper towel. Place each piece of cod on a small piece of parchment paper. Place the two pieces of fish in the pan, cover with a lid, reduce to low heat, and let the fish steam. Check the fish continuously by inserting a meat needle in the center of the fish and then touching it to your lip to see if it has warmed through. When the fish is warm in the middle, remove it and place it on a tea towel to drain.

Turn up the heat on the sauce and let it reduce slightly, seasoning it with salt, pepper, and possibly more lemon zest.

While the cod and green asparagus are being cooked, prepare the white asparagus. Slice the white asparagus into thin ribbons with a vegetable peeler. Place the thin ribbons in a bowl. Toss the asparagus ribbons in lemon juice, salt, and pepper. Let them marinate for about 10 minutes, then pat them dry to remove excess moisture.

In a small pot, heat some oil. When the oil is hot enough, add the capers and fry them until the oil no longer bubbles around them. Remove them and place them on absorbent paper.

The dish is now ready to be plated, see my picture for inspiration.