Heat the fat in a saucepan, add the chopped leek and risoni and sweat briefly, as well as the turkey ham cut into small cubes. Pour hot vegetable stock with a ladle and reduce the temperature so that it simmer gently. Add the lemon or lime juice.
As soon as the vegetable stock is halfway boiled, add some vegetable stock again. Repeat this process until the risoni have reached the desired consistency (I like it a bit firm to the bite). Add the thawed peas and stir in the yoghurt, season with salt and pepper as required.