In a skillet, sautee diced onion with 1 TBS cooking oil until softened. Add ground beef and brown thoroughly. Add in taco seasoning, water, and corn. Let simmer for 1-2 minutes. Turn off heat.
In a large bowl, add chopped lettuce, tomatoes, green onions, cilantro, olives, and cheese. Mix well.
Add salad dressing and meat mixture and mix again. Break up Doritos and mix in as well.
