Prepare the Mince Filling: Heat the olive oil in a large frying pan over a medium-high heat. Add the chopped onion and cook until softened and translucent, about 3-4 minutes, releasing a sweet aroma. Stir in the minced garlic and cook for another minute until fragrant. Add the beef mince to the pan, breaking it up with a wooden spoon. Cook until the mince is browned all over and no pink remains, which should take around 7-8 minutes. The meat will develop a lovely caramelised colour.

Season the Mince: Drain any excess fat from the pan. Stir in the smoked paprika, ground cumin, chilli powder, dried oregano, and cayenne pepper (if using). Cook for 1 minute, stirring constantly, allowing the spices to toast and become incredibly aromatic. Pour in the beef stock and bring to a simmer. Reduce the heat to low and let it gently simmer for 5-7 minutes, until the liquid has mostly evaporated and the mince mixture is thick and deeply flavourful. Season with salt and black pepper to taste.

Warm the Tortillas: While the mince cools slightly, gently warm the large and small tortillas in a dry pan over a medium heat for about 15-20 seconds per side, or microwave them briefly. They should feel pliable and soft to the touch, making them easier to fold without tearing. This step is crucial for assembly.

Assemble the Crunchwrap Base: Lay one large warm tortilla flat on a clean surface. Spread about a quarter of the sour cream in the centre, leaving a border. Spoon a generous quarter of the seasoned mince mixture over the sour cream. Drizzle a quarter of the nacho cheese sauce over the mince. Place one tostada shell directly on top of the cheese sauce.

Layer the Fresh Toppings and Fold: Spread another thin layer of sour cream onto the tostada shell. Top with a quarter of the shredded lettuce and a quarter of the diced tomato. Sprinkle a quarter of the shredded cheddar cheese over the vegetables. Place a small warm tortilla directly on top of all the fillings. Now, starting from one edge of the large tortilla, carefully fold the edges up and over the small tortilla, working your way around to create a sealed parcel. The folds should slightly overlap and meet in the middle, creating a neat, sealed seam.

Cook the Crunchwraps: Heat a large, dry frying pan or griddle over a medium heat. Carefully place one assembled crunchwrap, seam-side down, into the hot pan. Cook for 3-4 minutes until the tortilla is golden brown and crispy, with a pleasant toasted smell. Flip the crunchwrap over and cook for another 3-4 minutes on the other side until it’s also golden and the cheese inside has melted, creating a satisfying sizzle as it cooks. Repeat with the remaining crunchwraps. Serve immediately.