This recipe is from "Keepers: Culinary Treasures From the Heart," by Jo Dunbar Snow (Wimmer Cookbooks, $22.95).
1/2 cup olive oil
1/2 cup vegetable oil
3 tablespoons minced red onion
1 clove garlic, minced
1/2 cup rice vinegar
1 teaspoon Dijon mustard
1/2 teaspoon celery salt
Combine all the dressing ingredients in a covered jar. Allow to stand at room temperature for 24 hours. Refrigerate dressing one hour before serving.
For salad, place lettuce mix on flat serving plate. Arrange avocados symmetrically on top. Place onion in center and garnish with tomatoes.
When ready to serve, pour dressing over salad and mix.