In a large pot or Dutch oven, heat the olive oil over medium heat.
Add the onion and cook for 5-7 minutes, or until softened.
Add the garlic, cumin, coriander, cinnamon, ginger, smoked paprika, and cayenne pepper, and cook for 1-2 minutes, or until fragrant.
Add the sweet potatoes, chickpeas, diced tomatoes, and vegetable broth to the pot, and stir to combine.
Bring the mixture to a simmer, and then reduce the heat to low.
Cover the pot and simmer for 20-25 minutes, or until the sweet potatoes are tender.
Stir in the chopped cilantro, and season the stew with salt and black pepper, to taste.
Serve hot, garnished with additional cilantro, if desired.