Rinse chicken, pat dry, and cut into 1- to 1 1/2-inch pieces.
Put lettuce and tomatoes in a salad bowl. Pit and peel avocado. Cut into quarters, then thinly slice crosswise. Add to salad.
In a 10- to 12-inch frying pan over medium-high heat, stir bacon often until browned and crisp, 8 to 10 minutes. With a slotted spoon, transfer bacon to paper towels to drain. Discard all but 1 tablespoon fat from pan.
Add chicken to pan; stir often over medium-high heat until no longer pink in center of thickest part (cut to test), about 5 minutes. Remove from heat and stir in olive oil, vinegar, 1/4 teaspoon salt, and 1/4 teaspoon pepper.
Add chicken mixture and bacon to salad and mix gently. Add more salt and pepper to taste.
Wine pairing: A lean and fresh but creamy Pinot Gris perfectly balances the rich salad.
Note: Nutritional analysis is per serving.