In a large skillet over medium heat, add ground beef and cook until browned, about 5–7 minutes. Stir in taco seasoning and a splash of water, simmer for 2–3 minutes. Remove and cool.

Bring a large pot of salted water to a boil, add rotini pasta and cook until al dente, about 8–10 minutes. Drain and rinse under cold water, set aside to cool.

In a large mixing bowl, combine cooled pasta, seasoned beef, and diced vegetables: tomato, onion, corn, bell pepper, and jalapeño if using. Add shredded cheddar cheese and mix well.

Pour Catalina dressing over the salad and toss gently until everything is coated.

Just before serving, fold in slightly crushed Doritos to maintain their crunch.

For presentation, top with more uncrushed Doritos and optional fresh lettuce. Serve immediately.