Prepare vegetables by mincing garlic, chopping onion, and peeling and cubing sweet potatoes.
In a large saucepan, heat oil over medium heat and cook onion, garlic, chili powder, cumin, and cinnamon for 5 minutes or until softened.
Sprinkle with flour and cook, stirring, for one minute.
Add stock and stir until smooth.
Add sweet potatoes and tomatoes and bring to a boil.
Reduce heat, cover and simmer, stirring occasionally, for 20-25 minutes or until sweet potatoes are almost tender.
Add beans and green pepper and simmer uncovered for about 10 minutes or until potatoes are tender and chili is slightly thickened.
Season with salt and pepper to taste before serving.