2 lb. sirloin tip
1/2 c. chopped onion
2 tbsp. butter
2 tbsp. flour
2 beef bouillon cubes
1 1/2 c. water
2 tbsp. tomato paste
1 tsp. dry mustard
1 1/2 tsp. salt
Dash of pepper
1 (4 oz.) can undrained mushroom stems and pieces
1/2 c. sour cream

Cut meat into strips 1/2 inch thick; brown meat quickly in butter, turning to brown evenly. Remove meat, add onion and cook until clear. Blend in flour, cooking until lightly browned. Dissolve bouillon in water; slowly add to mixture. Cook until slightly thickened. Add tomato paste, seasonings, mushrooms and meat. Cover and simmer 30-35 minutes, or until tender. Fold in sour cream and cook just until thoroughly heated. Serve over cooked noodles. Yield: 6 servings.