Add vinegar and cook until pan is dry. Add stock or water and bring to a boil, stirring to scrape glaze from pan bottom. To this sauce add a pinch of salt and pepper. Add 2 tablespoons cold butter to sauce and whisk in. Remove from heat and whisk in remaining butter.
Place slices on plates and pour sauce around.
Serve with wild rice and a cooked vegetable, such as carrots. Preheat oven to 300 F. 2. Mix salt and pepper into flour. Dredge meat in flour to coat well. Shake off excess.