Cut the lettuce into the individual leaves, wash and spin dry. Pluck the leaves into bite-sized pieces. Cut the bell pepper, remove the white skin and seeds, wash and cut into strips. Rinse the tomatoes and cucumber, quarter the tomatoes, cut the cucumber lengthways and then cut into slices. Peel the onions and also cut them into slices. Stone the olives and cut the cheese into cubes. Put all the salad ingredients in a bowl and mix together. For the sauce, first mix the vinegar with the salt and pepper until the salt has completely dissolved. Then hide the oil. Pour the sauce over the salad just before serving. Fresh white bread and a Greek wine, for example, go well with this.