Put the spice paste ingredients into a small blender and whizz until smooth, adding a splash of water if you need to bring the paste together. In a heavy saucepan or casserole with a lid, heat the oil and fry the lamb all over. Season well.

Add the spice paste and fry for 3-4 mins until fragrant and coating the lamb. Top up with stock until just covered or transfer to a slow cooker (see tip, below). Add the bay leaves, cover with the lid and cook for 1-1 1/2 hrs until the lamb is very tender and shreddable. Top up with a little water during cooking if needed.

Remove the meat and shred with two forks and pour the liquid into a separate jug or bowl. Return the lamb to the pan and top with enough liquid to coat it but not make it soupy.

Heat a dry frying pan over a medium heat. Add a generous spoonful of the meat onto one half of the tortillas. Top with some mozzarella, onion and jalapeño. Sandwich together, folding the empty side over the filling, then cook in the pan for 2 mins on each side until golden, crisp and the cheese has melted. Serve with the remaining cooking liquid for dunking, and the lime, coriander, avocado and salsa on the table to let everyone help themselves.