Make the Dressing: In a small bowl, whisk together the mayonnaise, ranch dressing, and 1 tablespoon of warm (not hot) bacon grease until smooth.
½ cup mayonnaise, ¾ cup ranch dressing, 10 slices bacon
Cook the Pasta: Bring a large pot of salted water to a boil and cook the pasta according to package directions. Drain, rinse under cold water, and set aside to cool completely.
12 ounces rotini or penne pasta
Prepare Ingredients: While the pasta cools, dice the tomatoes, red onion, and avocado. Shred the cheddar cheese and crumble the cooked bacon.
1 ½ cups diced fresh tomatoes, ⅓ cup diced red onion, ½ avocado, 1 cup shredded cheddar cheese
Assemble the Salad: In a large mixing bowl, combine the cooled pasta, tomatoes, red onion, shredded cheese, and crumbled bacon.
Add the Dressing & Toss: Pour the dressing over the salad and toss everything together until evenly coated.
Add Avocado & Lettuce: Gently fold in the diced avocado and chopped romaine lettuce right before serving to keep them fresh and crisp.
1 cup chopped romaine lettuce
Garnish and Serve: Sprinkle with chopped parsley if using. Serve immediately.
Chopped fresh parsley
Make-Ahead Tip: If preparing in advance, store the salad and dressing separately. Add lettuce and avocado just before serving to prevent wilting and browning.