Peel, chop, and boil potatoes in salted water until about 80% done (10 minutes). Drain and set aside.
In a wide pan, heat olive oil over medium heat. Add onion, garlic, cumin seeds, black pepper, and Scotch bonnet. Sauté for 3 minutes.
Stir in Caribbean green seasoning and cook for 2–3 minutes.
Add curry powder and cook 3 minutes. Add 1/4 cup water to deglaze, scraping up any bits. Cook another 3–4 minutes.
Increase heat to medium-high and add chicken pieces. Stir to coat with curry base. Add salt.
After 3 minutes, add pre-boiled potatoes and spinach, then 2 cups water.
Bring to a boil, reduce to a rolling boil, and cook for 10 minutes until chicken is cooked through.
Taste and adjust salt. Simmer uncovered if you want a thicker gravy.
Serve hot with roti, rice, or bread.