Heat the olive oil and butter in a large pot over medium heat. Add the onion and cook until softened.
Add the sweet potato, garlic, and cinnamon. Cook for a few minutes until fragrant.
Stir in the chopped tomatoes, chicken stock, and sugar. Bring to a boil and then simmer for about 20 minutes.
While the soup simmers, prepare the dumplings. In a mixing bowl, combine breadcrumbs, baking powder, cheddar, mustard powder, oregano, egg, and cream cheese.
Form the mixture into small dumplings and drop them into the simmering soup during the last 10 minutes of cooking.
Finish the soup with fresh basil and single cream before serving.
Notes
You can add more herbs or spices to the soup according to your taste.