Pickle the celery: In a small saucepan, combine the apple cider vinegar, water, bay leaf, black peppercorns and salt, and bring to a boil. Place the celery in a heat-resistant bowl and pour the picking liquid over it. Allow to sit at room temperature until cool, at least 30 minutes.
In a 10-inch skillet, heat the olive oil over medium heat. Once the oil is hot, add the cherry tomatoes to the pan and let them cook undisturbed for 2 minutes, to create blisters on the tomatoes. Shake the pan to turn the tomatoes, then turn off the heat and let them sit for another 2 to 3 minutes. Season with salt and place the tomatoes in a small bowl to reserve. Wipe the skillet clean.
Season the chicken with salt and pepper. In a small bowl, combine the hot sauce, brown sugar and chicken stock. Place the skillet back over medium heat and add the butter. Once the butter is melted, place the chicken in the pan and cook for 1 minute on each side. Pour the hot sauce mixture over the chicken and bring to a boil. The mixture should come about halfway up the side of the chicken. Cover the pan, reduce the heat to a slow simmer and let cook for 30 minutes.
While the chicken is cooking, prepare the kale by tightly rolling several leaves together lengthwise, and using a sharp knife, cut the leaves into ¼-inch-thick ribbons. Divide the kale ribbons among your intended serving bowls.
After the chicken has cooked for 30 minutes, uncover the pan and use 2 forks to shred it, which should be easy to do. Once all the chicken is shredded, combine it with the sauce, raise the heat to medium and cook for about 5 more minutes. Using tongs, remove the chicken from the pan and place directly over the kale in each serving bowl. Add the toasted walnuts and blistered tomatoes to each serving bowl. Drain the celery of its pickling liquid and add to each bowl. Toss with Marie's® Chunky Blue Cheese Dressing and top with the chives to serve.