2 tbsp. butter
3/4 c. onion, thinly sliced
1/4 lb. fresh mushrooms, sliced
2 tbsp. all-purpose flour
1/4 tsp. ground marjoram
1/4 tsp. garlic salt
Salt & pepper to taste
3/4 c. beef broth
1/4 c. ketchup
8 slices leftover cooked roast beef

In a skillet, melt butter over medium heat. Saute onion for 5 minutes. Add mushrooms and saute 2 to 3 minutes. Stir in the flour and seasonings. Add broth and ketchup. Bring to a boil, stirring constantly. Reduce heat to low; simmer 10 minutes. Add beef and heat through. Yield 4 servings.