Heat the oven to 200C/180C fan/gas 6. Wash the skin of the pumpkin to remove any dirt or mud, then cut in half and scoop out the seeds and any stringy bits (reserve the seeds). Cut the pumpkin into chunky pieces, then tip onto a baking tray, drizzle with 1 tbsp oil and season. Toss to coat, then roast for 45 mins, stirring about halfway through.

Wash the seeds well, removing any stringy bits, then pat dry using kitchen paper. Put in a roasting tin, drizzle over a little oil and season with 1 tsp each of the cumin, ground coriander and paprika, and a little salt and pepper. Roast alongside the pumpkin for the final 10 mins, or until they pop and crisp up.

Meanwhile, heat the remaining 2 tbsp oil in a large saucepan over a medium heat and cook the onion for 5 mins until softened. Stir in the peppers and garlic, stirring for a few minutes. Add the tomato purée, chipotle paste, remaining cumin, ground coriander and paprika, the cinnamon, oregano, chilli flakes, chopped tomatoes, lentils, stock cube, sugar and vinegar, along with half a can of water (if cooking for 4). Season well, then cover and bubble gently for 30 mins until the lentils are cooked through, stirring occasionally.

Add the roasted pumpkin, all the beans and the chocolate to the chilli. Simmer for 5 mins until the beans have warmed through, then taste for seasoning. Once cool, will keep frozen for up to three months. Defrost thoroughly overnight and reheat until piping hot. Serve with rice or jacket potatoes, sprinkled with the pumpkin seeds and your choice of toppings, such as soured cream, coriander, sliced chillies, hot sauce, cheese, tortilla chips, and lime wedges on the side.