Add the cubed pumpkin, potato, onion and vegetable broth to the crockpot. Cook it on high for 4 hours. Blend with an emersion blender until smooth. Add in the coconut milk, curry powder, chili powder, and sugar. (Adjust the quantity of curry powder based on how spicy your seasoning is and how spicy you like your food. I added 1 tbsp. at a time and blended it thoroughly before tasting to assess the spice.) Then thoroughly mix and continue heating for about 20-30 minutes until the soup is heated through.
Garnish with salty roasted pumpkin seeds (see recipe below), shredded coconut, and a dollop of sour cream or yogurt. Salt and pepper to taste.