Clean, wash and dice the peppers. Peel onions and garlic and cut into cubes. Heat oil and stir-fry prepared vegetables until translucent. Add tomatoes, soy sauce and 1 litre of water.
Bring to the boil and simmer for about 20 minutes. Finely chop the soup with a hand blender. Season to taste with salt, pepper and sugar. Arrange the soup with 1 tbsp. crème fraîche on plates.