Heat the oven to 130C/110C/gas 1. Season the shoulder with salt, put in a roasting tin, cover with foil and cook in the oven for 5 hrs, until the meat is tender and coming away from the bone.

Meanwhile, make the taco dough. Mix the masa harina with a pinch of salt using your hands or a wooden spoon, then stir in the olive oil and around 100ml water to create a smooth dough. You may not need all the water. Roll into a ball, cover and chill until needed. Will keep covered and chilled for 24 hours.

For the adobo sauce, mix the blended chipotle with the soured cream to fully combine. Blitz all the green sauce ingredients in a blender or small food processor until smooth. Set both aside.

Once the meat is cooked and tender, remove from the oven and set aside to cool. Shred the meat using two forks.

Heat a non-stick or cast iron pan over a medium-high heat until hot. Split the taco dough into 10 pieces and roll into small balls, then roll each ball between two pieces of baking parchment to make a flat circle. Dry-fry in batches for 1 min on each side until lightly charred.

Serve the tacos with the meat piled on top, along with the diced avocado. Drizzle over a little lime juice and top with the adobo and green sauces, with extra on the side. Finish with slices of jalapeño, red onion and coriander leaves.