In a large mixing bowl, toss together the fresh lettuce, thinly sliced onions, chopped tomatoes, and creamy avocado with a tablespoon of lime juice, ensuring everything is evenly coated.
In a small bowl, whisk together the vinegar, tequila, an additional tablespoon of lime juice, salt, and pepper. Slowly drizzle in the olive oil while continuing to whisk until the dressing is smooth.
Drizzle the prepared dressing over the salad mixture and gently toss to combine. Serve immediately to enjoy the freshest flavors.