Heat the butter and oil, nuts and shallots steaming gently, add the diced sheepsfoot, salt and pepper, when mushrooms have released their water, they will be cooked, pass through a sieve mesh and keep the juice;
In a sauté pan, place a steamer, add the white wine, fish stock.
Cook monkfish medallions so they reach 68 ° C (158 ° F)
Add the mushrooms and adjust the moisture of the sauce with a little of the cooking juice of the monkfish, seasoned to taste;
Heat the puy lentils.
Divide the lentils among four plates, arrange the monkfish medallions and drizzle with mushroom sauce.