Carefully cut out the top of the squash and save the top for a lid while the soup cooks.
Scoop out seeds and set them aside.
Preheat the oven to 380℉ (190℃)
Melt the butter in a large frying pan over medium heat. Add the leek or onion and stir in the curry powder. Cook while stirring, for 2 or 3 minutes until the onions are just starting to soften.
Dissolve the Bouillon cubes in the hot water and add the stock to the onions and curry powder and mix to combine.
Place the hollowed out squash into a casserole dish with sides, to lightly support the squash and to catch any soup that may spill.
Add the remaining ingredients, except for the cream to the squash. Place the lid on top, and cook the soup in the oven for about an hour.
Remove the squash from the oven and scrape down the insides of the squash to be incorporated into the soup. Be careful not to penetrate the walls and cause the soup to leak out.
Place the soup back into the oven and cook it for another hour, or until the soup is completely cooked. Then use an immersion blender inside the squash to puree the soup before serving.
Place the squash on the table and enjoy the soup with cream and fresh crusty gluten free bread.