Wash the meat, dab dry and cut into 8 strips. Cut wooden skewers in half and skewer 1 piece of meat on each in a wavy shape. Season with salt and pepper. Peel garlic and chop finely. Clean, wash and cut leek into rings.
Peel and wash potatoes and cut into cubes. Heat clarified butter in a wide pot. Steam garlic in it until transparent. Add leek and potatoes and sweat for about 2 minutes. Season with salt and pepper. Take out some leek rings and put aside for garnishing. Deglaze with broth and simmer for 10 minutes. Puree soup and fold in mascarpone. Season to taste with salt, pepper and lemon juice.
Take out some leek rings and put aside for garnishing. Deglaze with broth and simmer for 10 minutes. Puree soup and fold in mascarpone. Season to taste with salt, pepper and lemon juice. Heat oil in a pan and fry skewers on each side for 1-2 minutes. Pour the leek soup into cups and garnish with leek and meat skewers