Preheat the broiler. Season the chicken with salt and black pepper; sprinkle with the brown sugar, paprika and cayenne. Warm the vegetable oil in a 12-inch ovenproof skillet over medium-high heat. Cook half of the chicken in the skillet until golden, 2 to 3 minutes per side; transfer to a plate. Cook the rest, then return all the chicken to the skillet. Add the wing sauce and bring to a simmer, then reduce the heat to medium and cook until the chicken registers 160 degrees F on an instant-read thermometer, about 10 minutes. Let cool, then shred and return to the skillet. Add more wing sauce if desired, then broil until crisp and caramelized, about 4 minutes.
Combine the carrots, celery and tomatoes in a bowl and season with salt and black pepper.
Make the ranch dressing: Combine the mayonnaise, buttermilk, garlic, dill, honey, mustard, 1/4 teaspoon salt and a pinch of black pepper in a bowl.
Split open the bread lengthwise. Put the blue cheese crumbles on the bottom, then add the chicken and veggies. Cut into small sandwiches and serve with the ranch dressing on the side.
Photograph by Con Poulos
Recipe courtesy Jeff Mauro for Food Network Magazine