Drain the chickpeas and place in a pot with twice as much water as chickpeas to cover. Add the garlic and bay leaf, bring to a boil and turn down to simmer for 1 hour.
Heat a large soup pot over medium heat and add the oil. Stir in the onion and cook for 5 to 7 minutes. Add sweet potato, cumin, red pepper flakes and tomatoes, and stir to coat the vegetables. Season with salt and pepper. Add the peanut butter, chickpeas and broth, stirring until all of the peanut butter is mixed in. Bring to a boil, cover and then turn to a simmer for 20 minutes.
Stir in spinach to wilt. Serve garnished with cilantro and chopped peanuts.