01 - Heat olive oil in a large skillet over medium-high heat. Add the finely chopped onion and sauté until translucent, about 2 minutes.
02 - Add minced garlic and cook for 30 seconds until fragrant. Add ground beef and cook until thoroughly browned, breaking it apart with a spatula, about 5 to 6 minutes.
03 - Stir in taco seasoning, tomato paste, and water. Simmer for 2 to 3 minutes until the mixture thickens. Season with salt and pepper to taste, then remove from heat.
04 - Warm the flour tortillas in a microwave or dry skillet until pliable and easy to fold.
05 - Lay each tortilla flat. Spread 2 tbsp of nacho cheese sauce in the center. Layer a quarter of the beef mixture over the sauce, then sprinkle with cheddar and Monterey Jack cheeses.
06 - Place a tostada shell on top of the cheese. Spread 1 tbsp of sour cream over the shell, then add shredded lettuce and diced tomatoes.
07 - Carefully fold the edges of the tortilla up and over the center, pleating as you go, until the filling is fully enclosed.
08 - Heat a large skillet over medium heat. Place each crunch wrap seam side down and cook for 2 to 3 minutes per side until golden brown and crisp.
09 - Slice each wrap in half and serve immediately while hot.