Step 1

For the marinade, crumble the achiote into the orange juice and leave for 5 minutes.

Step 2

In a dry pan over a medium heat, fry the chillies for 3-4 minutes or until charred, then add to a food processor with the achiote and orange juice, and the remaining marinade ingredients. Whizz to combine, then pour all over the meat. Cover and chill overnight or for at least 4 hours.

Step 3

Prepare the BBQ for direct cooking by spreading the coals in an even layer. Brush the pineapple and onion with a little oil, and cook for a few minutes, turning once, until charred. Dice, season and mix with the coriander.

Step 4

Grill the pork for 4-5 minutes on each side, turning, until the outside is charred but the meat on the inside is cooked through. (Alternatively, heat the grill to high and grill for 5 minutes each side, or until charred and cooked through.) Rest for 5 minutes under foil, then chop into small pieces, serving with the onion and pineapple, tortillas and lime wedges for squeezing over.