Drain and rinse the jackfruit thoroughly. Cut away the hard core pieces and any tough seeds, then use two forks to shred the remaining flesh into stringy pieces that resemble pulled pork.

Heat olive oil in a large skillet over medium heat. Add the diced onion and cook for 5 minutes until softened and translucent. Stir in the garlic, smoked paprika, and cumin and cook for 30 seconds until fragrant.

Add the shredded jackfruit, barbecue sauce, vegetable broth, and apple cider vinegar. Stir to combine, then reduce heat to low. Cover and simmer for 15-20 minutes, stirring occasionally, until the jackfruit is tender and the sauce has thickened and caramelized slightly.

Remove the lid and cook for 3-5 minutes more, stirring frequently, until the mixture is thick and sticky with some caramelized edges. Taste and adjust seasoning with salt or more vinegar if needed.

While the jackfruit simmers, combine the shredded cabbage and carrot in a bowl. Whisk together the mayonnaise, apple cider vinegar, celery seed, and salt, then pour over the vegetables and toss until evenly coated. Let rest for 10 minutes to soften slightly.

Toast the hamburger buns until golden. Pile a generous scoop of BBQ jackfruit on the bottom bun, top with a heaping spoonful of slaw, and add pickle chips if desired. Cap with the top bun and serve immediately.