In a mixing bowl or gallon-sized plastic bag, mix together the flour, garlic powder, mustard powder, chili powder, and pepper.

Add beef cubes and stir or shake to evenly coat pieces of meat.

Save any remaining flour mixture to be used a bit later.

In a Dutch oven or large, heavy-bottomed pot, heat oil until hot.

Add the beef cubes and cook for about 5 minutes, or until cubes are evenly browned on all sides, stirring occasionally.

Add the tomatoes, broth, Worcestershire sauce, carrots, and onions.

Bring to a boil and then reduce heat to maintain a low simmer.

Cover and cook for 1-1½ hours or until beef is tender, stirring occasionally.

Stir in zucchini and corn and continue to simmer, covered, for another 15-20 minutes.

In a small bowl, blend together the reserved flour mixture and water until smooth.

Add to stew and cook, stirring for several minutes or until the stew has thickened.