2 lbs. sirloin steak, cut in 1 inch thick
2 c. fresh mushrooms, sliced
1 c. onions, chopped fine
1/4 c. butter or shortening
3 beef bouillon cubes
1 c. boiling water
2 tbsp. tomato paste
1 tsp. dry mustard
1/2 tsp. salt
2 tbsp. flour
1/2 c. water
1 c. dairy sour cream
4 c. rice, cooked

Cut steak into strips 2 1/4 inch long. In large skillet, saute mushrooms and onions in 3 tablespoon butter until golden brown. Remove from skillet. Add remaining 1 tablespoon butter, brown meat on all sides for 15 minutes. Dissolve bouillon cubes in boiling water, pour over meat. Add tomato paste, mustard and salt. Simmer 45 minutes until tender. Combine flour and water. Slowly pour in meat mixture. Cook, stirring constantly, until mixture comes to a boil. Reduce heat. Add mushrooms, onions and sour cream. Heat but do not boil. Serve on hot rice.

NOTE: The flavor improves if stroganoff is prepared the day before. Add the sour cream when reheating.