Filet with Mustard Sauce

Halve filet crosswise. Heat oil in a skillet. Add filet halves and cook on both sides to desired doneness. Reserve filets on a plate covered with foil. Add cognac or brandy to skillet to deglaze, scraping up brown bits. Add broth and water and boil until reduced to 1/4 cup. Remove from heat and whisk in mustard, butter and pepper. Pour sauce over filets to serve.