Remove any seeds from the jackfruit and cut any large pieces in half.
Heat the oil in a saucepan over a medium heat. Add the chopped onion and cook, stirring, for 5 minutes until softened. Add the crushed garlic and cook for another 1 minute.
Add the thyme and jerk spice mix, stir, then add the jackfruit, barbecue sauce, vinegar, chopped tomatoes and 150ml water. When the sauce starts to bubble turn the heat to low, cover with a lid, and simmer for 30 minutes. Stir the sauce every now and then to stop it sticking to the bottom of the pan.
Take the lid off and cook for another 5 minutes until the sauce has reduced and thickened.
Preheat the oven to 220C/425F/Gas 7. Line a large baking tray with baking paper.
Spoon the jackfruit onto the lined baking tray. Now the fun bit! Using two forks, pull the jackfruit into strips, so it looks shredded. Add a splash of water to the sauce in the pan and spoon the mixture over the shredded jackfruit until coated. Place in the oven for 15 minutes until starting to crisp up at the edges.
Serve the barbecue jackfruit with any spare sauce spooned over (heat it up first) with wedges, chips or in a wrap.