Avocado Tomato Salad

2 ripe avocados, peeled and sliced
2 large tomatoes, cut into wedges
1 medium onion, cut into wedges
1 cup Italian salad dressing
Lettuce leaves, optional

In a bowl, combine the avocados, tomatoes and onion; add dressing and stir to coat. Chill for 20 to 30 minutes. Serve over lettuce leaves if desired. Makes 6-8 servings.