Serves 6 to 8
2 lbs (900g) beef tenderloin
¼ cup (50ml) Dijon mustard
1 tsp (5ml) coarsely ground pepper
For the sauce:
2 tsp (10ml) butter
3 cups (750ml) finely chopped mushrooms
2 tsp (10ml) all-purpose flour
3 tbsp (50ml) chopped green onions
1 cup (250ml) canned beef broth (undiluted)
½ tsp (2ml) died tarragon leaves
½ cup (125ml) cream
Trim beef of any visible fat; place in roasting pan. Stir mustard with pepper then spread over beef. Let stand at room temperature 1 hour.
Preheat oven to 425, roast beef for 10 minutes then reduce heat to 350 and roast for 25 minutes for medium-rare (likely less), 30 to 35 for well-done. Remove from oven; let stand 10 minutes before slicing.
To make the sauce, in a skillet, heat butter over high heat; cook mushrooms, stirring often (about 8 min) until lightly browned. Sprinkle with flour; cook 1 minute.
Add onions; cook stirring for 1 minute. Add beef broth and tarragon; bring to boil. Boil, stirring often, until liquid is reduced by half.
Stir in cream and bring to a boil. Reduce heat to medium-high, boil, stirring 2 to 3 minutes or until thickened slightly and sauce is reduced to about 1 cup.
Spoon sauce over servings of beef.
Tip: Sauce may be made ahead and refrigerated for up to one day. Reheat before serving.