Cumin contains essential oils, which on the one hand provide for its intensive taste and on the other hand have a positive effect on digestion. They stimulate the formation of digestive juices, prevent flatulence and are good for the intestinal flora.
Instead of rice, you can also use chopped potatoes and refine the soup with other herbs as desired.
Preheat oven to 180°C (approximately 350°F). Cut pumpkin into 2 cm (approximately 3/4 inch) cubes and place in an oven-proof dish. Mix cumin, turmeric and marjoram with the oil. Drizzle over pumpkin cubes. Pour 150 ml (approximately cup 5 ounces) of water into the dish and bake pumpkin in the oven until soft, about 35 minutes. Cook rice according to package directions in boiling salted water, drain and allow excess moisture to drain. Trim leeks, rinse and cut crosswise into thin rings. Heat butter in a large saucepan and sauté leeks briefly. Add pumpkin cubes and cooking liquid and puree with an immersion blender.
Add chicken broth to leek-pumpkin puree. Add rice and sherry and return to a boil. Season soup to taste. Serve soup in glasses sprinkled with herbs.