Soak bread in milk for at least 1 hour.

Cook the celery and leeks in the butter until slightly brown. Add the sausage and sauté, stirring until the sausage is fully cooked and slightly browned.

Put milk-soaked bread in a large bowl. Add the eggs, sausage mixture, and some chopped parsley and mix well. Start adding flour/Panko to the mix until you have a texture that’s sticky but firm. It needs to hold the shape of a ball. Add Fontina cheese.

Dust hands with flour, scoop up mix and roll into small balls (about 1 rounded tablespoon each).

Drop balls into boiling chicken stock and cook for 10 minutes. Remove balls from stock and reduce liquid by half.

Place 3 balls in each bowl and cover with reduced chicken stock. Sprinkle with Parmesan and chopped parsley and serve.