In a mixing bowl, combine the flour, garlic powder, onion powder, salt, and pepper. Mix well.
Dredge each cubed steak in the flour mixture, shaking off the excess flour.
Heat the vegetable oil in a large skillet over medium-high heat. Once hot, add the cubed steaks and cook for 3-4 minutes per side, or until they are browned. Remove the steaks from the skillet and set aside.
In the same skillet, add sliced onions and sauté for about 5 minutes, or until they are soft and translucent.
Gradually add the beef broth to the skillet, scraping the bottom to release any browned bits. Stir in Worcestershire sauce and thyme.
Return the cubed steaks to the skillet, ensuring they are submerged in the gravy. Bring to a simmer.
Reduce the heat to low, cover, and let cook for 30 minutes, or until the steaks are tender and the gravy has thickened.
Serve warm over mashed potatoes or rice, spooning the onion gravy on top.