Firm ripe tomatoes
Mozzarella cheese
Vinaigrette (2/3 fine olive oil + 1/3 tarragon vinegar)
Red Italian onions
Oregano

Slice the tomatoes and layer with the onions sliced thinly. Add the Mozzarella, cut into bite size cubes. Sprinkle with the oregano and then the vinaigrette. Refrigerate several hours but remove from the refrigerator at least an hour before serving. There are no quantities given as the amounts are all a matter of choice.