Begin by seasoning the chicken breasts with black pepper and a pinch of kosher or sea salt. Heat 1 tablespoon of olive oil in a large skillet over medium-high heat. Once the oil is hot, add the chicken breasts and cook for about 6-7 minutes on each side, or until fully cooked and no longer pink in the center. Use a meat thermometer to check that the internal temperature reaches 165°F. Remove the chicken from the skillet and let it rest.
In the same skillet, add the remaining tablespoon of olive oil. Toss in the sliced sweet onions and mushrooms. Cook over medium heat, stirring occasionally, until the onions are golden brown and caramelized, about 10-15 minutes. The mushrooms should also be tender. If they start to stick to the pan, you can add a splash of water to deglaze the skillet.
While the onions and mushrooms are caramelizing, shred the cooked chicken using two forks. Once the onions are caramelized, reduce the heat to low and add the shredded chicken to the skillet. Pour in the barbecue sauce, stirring until everything is well coated and heated through, about 3-5 minutes.
Slice the whole-wheat buns in half, and fill each with a generous scoop of the BBQ chicken mixture. Top with a spoonful of the caramelized onions and mushrooms. If you’re using the creamy cabbage and bok choy slaw, add a handful for that extra crunch.
Arrange the sliders on a serving platter and enjoy immediately while they’re warm. These sliders are perfect for sharing, so gather your loved ones and dig in!
