Clean, wash and chop the peppers. Peel, quarter, core and dice three apples. Peel and dice the onion.
Fry the onions in hot butter. Add the peppers and apples, fry for approx. 4 minutes, season, pour in the stock, bring to the boil and simmer for approx. 15 minutes.
Toast the pumpkin seeds in a pan without fat. Roughly pluck the basil. Puree the soup with the electric cutting stick and season to taste.
Wash the rest of the apple and grate it into narrow strips. Serve the soup with apple strips, pumpkin seeds and basil. Drizzle with a few drops of olive oil if desired.