Heat olive oil in a large pot or Dutch oven over medium-high heat. If using chicken, add chicken pieces and cook until browned on all sides, about 5-7 minutes. Remove chicken and set aside. If using chickpeas, no pre-cooking is needed at this stage.

Reduce heat to medium. Add chopped onion to the pot and cook until softened, about 5 minutes. Add minced garlic and grated ginger, and cook for another minute until fragrant.

Stir in ground cumin, coriander, turmeric, and paprika (if using). Cook for 30 seconds, stirring constantly, until aromatic.

Stir in the tomato paste and cook for 1-2 minutes, allowing it to slightly darken.

Pour in the vegetable or chicken broth and scrape up any browned bits from the bottom of the pot. Bring the mixture to a gentle boil. If using chicken, return the cooked chicken to the pot. If using chickpeas, add them now.

Reduce heat to low, cover, and simmer for 15-20 minutes, or until the chicken is cooked through and tender, or the flavors have melded if vegetarian. Stir in the fresh spinach a handful at a time, allowing it to wilt before adding more. Cook until all spinach is wilted, about 2-3 minutes. Season with salt and black pepper to taste. Serve hot with rice or bread.