In large cooking pot, saute onion and garlic in oil on low-medium heat until tender.
Add lime zest, 1/2 lime juice, chili powder, cinnamon, and cumin. Cook with lid covered for about 15 minutes, adding a small amount of water or oil if content starts to stick to the bottom of pot.
Add sweet potatoes, tomatoes, black beans, chipotle chiles, cilantro and cook until potatoes are tender.
Add remaining lime juice and more spices to taste. Keep covered, and simmer for 15 minutes, adding a bit more water as needed.

3 tablespoon olive or cooking oil
6 cloves garlic, chopped
2 medium white or yellow onions, diced
2 4-ounce cans diced green chiles
2 medium sweet potatoes, peeled and chopped into small cubes
1 28-ounce can whole tomatoes, chopped
4 15-ounce can black beans, drained
2 chipotle chilis, chopped
1 large lime, juice & zest
2 tablespoon chili powder
2 tablespoon ground cinnamon
2 tablespoon cumin
1 cup fresh cilantro, chopped
filtered water