For Your Next Summertime Picnic

3 sweet onions, such as Walla Walla or Vidalia, sliced and separated into rings

3 ounces mozzarella cheese, grated (optional)

Make the dressing: combine oil, vinegar, basil, parsley, salt, mustard and sugar and mix well.Layer the tomatoes and onions in large bowl (clear glass makes a pretty presentation), pour dressing over all, and marinate at least 4 hours. Serve on large lettuce leaves, and add grated cheese, if desired.