Step 1Heat a large sauté pan over medium heat until hot. Add the oil to the pan, then add the onions. Cook the onions until they are translucent and just start to brown, about 4 minutes.
Step 2Add the ground beef to the pan. Mix the ground beef with the onions until well mixed. Add the cumin, chile powder, onion powder, garlic powder, ancho chile powder, ground chipotle powder, salt and sugar to the pan and mix well. Cook the meat until it browns, about 5 minutes. Remove from heat and set aside.
Step 1Toss the cheese and corn starch together in a medium sauce pan. Add the evaporated milk and stir.
Step 2Heat over medium heat until the mixture thickens to a sauce, about 5 minutes, stirring frequently. Remove from heat. This makes about 11/2 cups sauce.
Step 1To assemble the crunchwraps, lay out each of the tortillas. Evenly divide the taco meat among the tortillas, spooning a small circle on top of each tortilla. Top each mound of taco meat with a tostada, then evenly divide the shredded lettuce, cheese sauce, tomato and diced olives. Top each with a heaping tablespoon of sour cream.
Step 2Carefully fold the outer edges of each tortilla toward the center, creating a circular package using five folds.
Step 3Heat a skillet over medium heat until hot. Toast each crunchwrap until golden brown, about 1 minute on each side. Serve immediately with the hot sauce.