Preheat the oven to 350 degrees. Spray a 9 by 12 inch (or similar) baking dish with cooking spray.
Heat the oil in a large skillet over medium-high heat. Add the onion and cook, stirring occasionally, until tender, about 3 minutes. Add the jackfruit and barbecue sauce, bring to a simmer, and cover. Cook, covered, until the jackfruit is tender, mashing with a potato masher or fork occasionally, about 5 minutes. Add the corn and black beans, stir.
Place the chips in the bottom of the prepared dish. Top with half the queso. Top with the jackfruit mixture then the rest of the queso. Scatter the tomato halves all over the top.