Brown and season the ground beef in a medium skillet over medium-high heat. Drain most but not all fat to leave flavor behind.

Cook the rotini according to package directions until al dente. Drain and rinse under cold water to stop cooking and cool the pasta quickly.

Chop the veggies and shred the lettuce.

In a large mixing bowl, combine the cooled rotini, seasoned beef, chopped pepper, diced onion, halved grape tomatoes, shredded cheddar, and shredded iceberg lettuce.

Whisk together the French dressing and sour cream, then pour over the salad. Toss gently until evenly coated.

Fold in most of the crushed Doritos, reserving a handful for garnish. Top with an extra dollop of sour cream if desired. Serve immediately.