In a large pot, heat oil over medium heat. Saute onions, garlic, carrots, celery, and zucchini until slightly softened, 5 minutes.
Drop meat into the pot and break apart using a wooden spoon. Cook until meat is cooked thoroughly and browned. Stir in the remaining ingredients and bring to boil. Reduce heat to low and simmer at least 20 minutes but up to 3 hours. If you notice chili is getting too thick or is sticking to the bottom of the pot, add in an extra splash of water or beef stock.