Brown beef and onion in a large skillet over medium-high heat for 8 to 10 minutes, breaking the meat into fine crumbles, until it reaches 160°F. Spoon off excess fat.
Stir in ancho chile, cumin, garlic powder, salt and tomato paste for 1 minute. Add water and simmer for 3 to 4 minutes until the liquid lightly coats the beef, then stir in vinegar.
Divide corn chips among 6 plain food cups or small bowls immediately before serving. Keep the chips dry until the beef and toppings are ready.
Spoon one-sixth of the hot beef over each cup of chips and scatter with one-sixth of the cheddar. Add lettuce and drained tomato over the meat.
Top each serving with 1 tablespoon sour cream and serve immediately with a spoon, leaving any unused toppings chilled and the chips separate.