Heat the oil in a large pot over medium heat. Add the onion, bell pepper, and salt and cook, stirring occasionally, until the onion is translucent, 5 to 8 minutes. Add the garlic and chili powder and cook, stirring, for 30 seconds, until fragrant.

Add the beans, bean liquid, tomatoes, green chiles, maple syrup, and a few grinds of pepper. Reduce the heat to low and simmer uncovered for 20 minutes, stirring occasionally, until the chili has thickened.

Stir in the lime juice and season to taste with more salt, pepper, chili powder, and cayenne, if desired. Serve with lime wedges and desired toppings.