Cook the Ground Beef
Heat a large skillet over medium heat. Add the ground beef and cook until fully browned, breaking it into crumbles with a spatula.
Stir in the taco seasoning and prepare according to the packet instructions. Remove from heat and let cool slightly.
Prep the Vegetables
Wash and chop the lettuce, dice the onion, and halve the cherry tomatoes.
Assemble the Salad
In a large mixing bowl, combine the lettuce, tomatoes, onion, and shredded cheese.
Add the slightly cooled taco beef to the bowl.
Add Doritos and Dressing
Just before serving, sprinkle the crushed Doritos over the salad.
Drizzle the Catalina or ranch dressing over the top and toss gently to combine.
Serve
Portion into bowls or plates and serve immediately.