Lay a large flour tortilla flat on a clean surface. Spread a layer of nacho cheese sauce in the center of the tortilla.
Add a scoop of the seasoned beef on top of the cheese sauce.
Place a tostada shell (or crispy corn tortilla) on top of the beef. Spread a thin layer of sour cream over the tostada shell.
Sprinkle shredded lettuce, diced tomatoes, and shredded cheese on top of the sour cream.
To fold the crunch wrap, start at the bottom of the tortilla and fold the edge up to the center. Continue working your way around, folding as tightly as possible, until the filling is completely enclosed.