Mix flour, eggs, milk and 1 pinch of salt with the whisk of the hand mixer until smooth. Leave to swell for about 15 minutes. Clean, wash (if necessary) and slice the mushrooms.
Peel and finely dice the onion. Peel and slice the garlic. Wash the rocket, spin dry and chop coarsely, except for a little bit for garnishing. Chop the nuts coarsely. Heat 2 tablespoons of oil.
Fry the mushrooms for about 10 minutes, turning them over. After 4 minutes add garlic, onion and nuts. Stir in crème fraîche 2 minutes before the end of cooking time and season with salt and pepper. Fold in the rocket.
Heat 2 tablespoons of oil in portions in a frying pan (20 cm Ø). Bake 4 pancakes one after the other. Fill the pancakes with the mushroom pan and arrange on plates. Garnish with remaining rocket.