In a large Dutch oven, warm the oil over medium heat. Add the onion and garlic and cook until softened, about 5 minutes. Add the jalapenos, ground cinnamon, cumin, smoked paprika, and cook for another 2 to 3 minutes so the spices become fragrant.
Add the tomatoes, tomato sauce, stock, lentils, kidney beans, butter beans, walnuts, chocolate, and cinnamon sticks. Taste test while simmering; take out the cinnamon sticks when the desired flavor is reached or leave in for the full cooking time (I prefer this).
Simmer over medium-low heat for 2 hours or more, until thickened. You may adjust the cooking time depending on how thick you like your chili. If you prefer it on the thin side, add more stock. Add salt and pepper, to taste.
Before serving, pick out the cinnamon sticks and adjust seasonings…