1. Place olive oil into a large soup pot set at medium-high and let warm. Then, add the onions and let cook for 3 minutes or so, stirring occasionally.
2. Add the ground beef. Using a spatula, break the meat up into small pieces. Brown until no pink is left (probably around 7 minutes). Stirring occasionally.
3. Add in the chili powder, cumin, tomato paste, garlic powder, salt and pepper. Stir.
4. Add beef broth, tomatoes (including the juice), celery and tomato sauce. Stir well.
5. Raise the temperature until the liquid just begins to boil. Then, reduce heat to low-medium and let simmer, uncovered, for 25 minutes.
6. Remove from heat and let cool for 5 minutes. Serve with desired toppings.