Preheat oven to 375°F.
Bake bacon on a slotted pan or metal rack set on a rimmed baking sheet to very crisp. Cut slices into thirds.
Place avocado in a food processor and add lemon or lime juice, vinegar, olive oil, Tabasco, sour cream or yogurt, garlic, herbs, salt and pepper. Pulse into a dressing and transfer to a serving bowl.
Arrange lettuce on a large serving platter and top the lettuce with onions, tomatoes, eggs, chicken, blue cheese and bacon. Working in any arrangement you like, set stripes of each ingredient or place them in a scattered pattern. Serve dressing alongside.