To make the dressing. Combine all ingredients in a glass jar and whisk until smooth. Season with salt and pepper.Bring a large pot of salted water to a boil. Boil the pasta to al dente, according to package directions. Drain. In a large bowl, toss together the pasta, lettuce, mozzarella, tomatoes, cheddar, and avocado. Pour over the dressing and toss well to combine. Serve warm or cold. The salad will develop more flavor as it sits.