Filet Mignon with Red Wine Sauce

3 c. dry red wine
3 tbsp. cognac
3 shallots, chopped
1 tsp. thyme
6 filet mignon steaks
4 c. beef stock

Whisk first 4 ingredients in large bowl. Marinate steaks overnight in glass pans. Remove steaks from marinade and pat dry. Cook steaks in oven, pan or barbeque. Transfer marinade to saucepan. Boil about 20 minutes to reduce to 1 cup. Add stock and boil about 20 more minutes to reduce to 1 1/4 cups. Add 5 tablespoons of chilled butter to sauce and spoon over steaks. Serves 6.