In a small saucepan, combine 1 cup apple cider, 2 tablespoons honey, 1 tablespoon Dijon mustard, and 2 cloves minced garlic. Simmer over medium heat, stirring occasionally, until the mixture reduces and thickens into a sticky glaze that coats the back of a spoon.

Heat 1 tablespoon cooking oil in a skillet over medium-high heat. Season the chicken thighs generously with salt and pepper. Place them skin side down and sear until the skin is golden and crisp, about 5-7 minutes. Flip and continue cooking for another 5 minutes until chicken is almost cooked through.

Pour the prepared apple cider glaze over the chicken in the skillet. Reduce the heat to medium-low and cook gently, spooning the glaze over the thighs frequently, until the glaze becomes sticky and caramelized, coating the chicken beautifully.

While the chicken cooks, combine shredded green cabbage, shredded carrots, and thinly sliced apple in a large bowl. In a small bowl, whisk together 2 tablespoons apple cider vinegar, 1/4 teaspoon celery seeds, salt, and pepper. Drizzle this dressing over the slaw and toss gently to combine. Finish by stirring in chopped fresh parsley or chives for brightness.

Arrange the sticky apple cider chicken thighs on plates alongside a generous portion of the crisp autumn slaw. Serve immediately.