Peel and wash the asparagus and cut off the woody ends. Cook the asparagus in boiling salted water with a pinch of sugar for 15 to 20 minutes. In the meantime, wash the fish, sprinkle with lemon juice and season with salt.
Clean and wash the spring onions. Cut the upper halves into fine rings. Cook the rest with the asparagus for the last two minutes. Chop the peanuts. Coat fish with mustard and press leek and onion rings on top.
Overfold the fillet and fix it with a wooden stick. Spread with crème fraîche and turn in chopped peanuts. Fry in hot clarified butter over medium heat for about six minutes on each side.
Finely chop the olives for the marinade. Mix with vinegar and oil. Season to taste with salt and pepper. Wash herbs, dab dry and chop finely. Sprinkle asparagus and spring onions with the marinade and serve with the fish.
Sprinkle with herbs and garnish with lemon. New potatoes taste good with it.