Peel the onion, cut into small cubes and sauté in butter until translucent.
Add the peas, sauté briefly, then add the vegetable stock.
Cover and simmer over a mild heat for about 10 minutes.
Season the lamb salmon with salt and pepper and fry in very hot oil for about 4 minutes on each side. Then immediately wrap in aluminum foil and let rest for 10 minutes.
Deglaze the roast with the wine and stir in the crème fraiche.
Salt and pepper.
Finely chop the mint. Add the cream to the peas and puree finely in the broth.
Season with salt, pepper, nutmeg, lemon juice and the mint.
Cut the meat into thick slices and arrange on a preheated plate with the sauce and puree.