Start with the leek, wash it carefully and cut it into rounds. Cook it together with a drizzle of oil in a large skillet over low heat; add salt to taste.
Remove the casing from the sausage, shell it, and add it to the leek. Brown it all for about 10 minutes.
Combine saffron with hot cooking cream, stir and set aside.
Cook the pumpkin potato Chicche by boiling them in salted boiling water, as directed on the package. Once cooked, drain the grits directly into the leek and sausage sauce; stir a few moments so that the flavors recognize each other.
Plate the pumpkin potato Chicche with sausage and leek, finishing with the saffron cream, a grind of black pepper, and a few sprigs of rosemary to scent.