Heat oil in a large Dutch oven coated with cooking spray over medium-high heat. Add yellow onion and next 6 ingredients (through garlic) to pan; sauté 5 minutes or until vegetables are tender. Add 1 cup broth, scraping pan to loosen browned bits. Add remaining 1 cup broth and carrot; sauté 5 minutes.
Pierce habanero with a fork; add to pan. Stir in squash, tomato, and zucchini; bring to a boil. Reduce heat, and simmer 10 minutes. Discard habanero; simmer 15 minutes or until vegetables are tender.