3 tbsp. butter
1/2 c. chopped onion
1 lb. boneless steak, cut into thin strips
1 c. sliced fresh mushrooms
Big pinch whole thyme leaves
1/2 tsp. salt
1/4 tsp. pepper
3/4 c. beef broth
3 to 4 tbsp. flour
1/2 to 1 c. sour cream or yogurt

Combine butter and onion in a 10 inch round baking dish. Microwave uncovered high for 4 to 5 minutes or until onion is soft, stirring once. Add beef, mushrooms and seasonings. Microwave uncovered, on high for 10 to 12 minutes or until beef is tender, stirring twice.

Drain liquid from beef into a 2 cups measure. Add enough beef broth to measure to equal 3/4 cups set aside, stir flour into meat, blending until smooth. Slowly add juice and broth mixture.

Stir, microwave uncovered, on high 2 to 3 minutes, or until sauce is thickened, stirring once. Stir in sour cream or yogurt. Microwave on low and defrost for 4 to 5 minutes, stirring every minute. Do not let sauce boil or sour cream will curdle.