In a non-stick frying pan, heat half the oil at high heat. Salt and pepper the cutlets and sear them, 2 at a time, 1 minute on each side, turning only once. Remove cutlets from heat and place on a serving platter and keep warm.
Add butter to the same frying pan and sauté mushrooms and shallots at high heat, stirring from time to time for 5 minutes, or until the cooking juices have completely evaporated.
Deglaze the frying pan with the chicken stock, scraping the pan with a wooden spoon to loosen the drippings. Let the liquid boil down to half, and then add the evaporated milk. Stir in the Dijon mustard and continue cooking for 3 minutes or until the sauce has a nice consistency.
Pour the sauce over the cutlets and serve with a side of pilaf rice and a green vegetable.