a medium saucepan, bring beef broth to a boil.

Add onion and garlic powder, ketchup, minced garlic and sliced onion.

When broth comes to a rolling boil remove from heat, drop in the separated sliced roast beef

After 2-3 minutes remove roast beef from broth using a slotted spoon.

Return broth to stove on high setting and sprinkle flour over surface, stirring briskly to avoid lumps.

Simmer over medium heat 5 minutes (or until it thickens).

During the last minute, drain and add the sliced mushrooms.

Place some Roast beef on a sliced kaiser roll or similar bread, close the sandwich if desired.

Pour some gravy over roast beef and bread .

Season to taste with salt and pepper.