Mix together the chili powder, paprika, salt, cumin, coriander and cayenne in a small bowl and set aside.
Pat the beef dry with paper towels. Heat a large cast iron skillet over medium heat, add the oil and heat through. Add the ground beef and cook, stirring occasionally and using a wooden spoon to break up the meat, until the beef is browned, about 6 minutes.
Add the seasoning mixture as well as 1/3 cup water. Stir to combine and remove from heat.
For the nacho cheese sauce:
Heat a medium saucepan over medium heat, add the butter and allow to melt. Whisk in the flour and cook, stirring constantly until the mixture is a pale brown, about 30 seconds. Whisk in the milk and bring to a simmer, whisking occasionally until the mixture thickens, about 10 minutes.
Slowly stir in the Cheddar, pepper jack cheese and red pepper until completely melted.
For assembly:
Heat a large nonstick skillet over medium-low heat.
Working one at a time, lay one of the large tortillas down on a clean workspace. Add about ½ cup of the ground beef into the center of the tortilla (keeping the meat into an area the size of the smaller tortillas) then top with about ¼ cup of the nacho cheese sauce.
Top with one of the tostada shells. Top with sour cream (if using), some of the lettuce, tomato, Cheddar and Monterey jack cheese. Add one of the smaller flour tortillas on top.
To fold the crunch wrap, start by gathering the top edge up and over the center and the fillings. Continue to work your way around the tortilla continuing to fold, keeping everything as tight as possible.
Lightly grease the pan with some of the vegetable oil. Place the crunch wrap seam-side down in the pan. Use a cast iron press or a brick wrapped in aluminum foil to weight the crunch wrap down in the pan.
Cook until the tortilla is golden brown, for 2 to 3 minutes. Flip and continue cooking until the other side is golden brown, about an additional 2 to 3 minutes. Serve immediately with hot sauce of choice.