In a medium pot or sauce pan, heat olive oil over medium heat. Add the pumpkin seeds and toast for about 2-3 minutes, or until they begin to brown. Add the leeks and parsnips, and cook until the leeks begin to wilt. Add the apple, season with salt and pepper, and add the cumin, coriander and paprika. Cook for about 2 more minutes, then stir in the chicken stock. Bring to a boil.
Transfer the soup to a blender (working in batches if necessary), and blend until the soup is smooth. Pour the soup into bowls and serve garnished with pumpkin seeds.