Pickled Onions: In a small mixing bowl combine finely sliced red onion with 2 tbsp vinegar & lime juice and a pinch of salt. Leave to pickle for as long as you have time for, tossing every so often. The longer you leave them the softer/more acidic they'll be.
Quick Guac: In a small mixing bowl add avocado, 2 tbsp coriander/cilantro, 1 tbsp lime juice, a pinch of chilli flakes (optional) and a good pinch of salt. Smash with a fork or potato masher, then place to one side.
Prep Chicken: In a small pot combine 1 heaped tsp smoked paprika & cumin, 1/2 tsp oregano, onion powder, garlic powder & salt, 1/4 tsp cayenne pepper and a pinch of black pepper. Sprinkle over chicken thighs, then drizzle over 2 tbsp olive oil. Use your hands to fully coat the chicken thighs.
Cook Chicken: In a large pan over medium-high heat add your chicken thighs. Leave to fry until they begin to char, then flip and continue frying until they're cooked right through the centre and lightly charred on the other side. If they look like they're charring too fast turn down the heat slightly once you flip. Remove from pan and place in a bowl to one side.
Chicken Sauce: Turn heat to medium and add 1 tbsp tomato paste. Stir and fry for 1-2mins, then add 1 cup chicken stock and 1 tbsp lime juice & honey. Give it a good stir then simmer for 5mins, or until it begins to thicken. Shred chicken with two forks, then add to the sauce and simmer for another couple of mins, until the chicken soaks up the sauce.
Tostadas: Stack your tostadas in this order: Tostada Shell -> Refried Beans -> Guac -> Chicken -> Cheese -> Pickled Onions -> Coriander/Cilantro. Be careful when stacking that you don't break the shells, especially when you spread the beans/guac.