Heat the olive oil over medium heat in a large pot or Dutch oven. Add the onions, carrots, and celery. Cook, stirring occasionally, until the vegetables begin to soften, about five minutes. Add the zucchini and continue to cook for another two to three minutes.

Stir in the kidney beans, pinto beans, diced tomatoes with juice, and butternut squash. Pour in the vegetable broth or water, then add the spices. Stir everything together.

Bring the mixture to a boil. Once boiling, reduce the heat to low and let it simmer, uncovered, for 40–50 minutes or until the butternut squash is tender, stirring occasionally.

About 10 minutes before serving, stir in the lime juice and cilantro (if using). Adjust seasoning if needed.

Ladle the chili into bowls and top with your choice of toppings. Serve with a side of cornbread or crusty bread.