Prepare the Chicken

Combine the chicken thighs, vegetable oil, 1 teaspoon of garlic powder, onion powder, sweet paprika, smoked paprika, and 1 teaspoon of red-pepper flakes in a 6- to 8-quart slow cooker. Season the mixture generously with kosher salt and freshly ground black pepper. Stir until the chicken is evenly coated with the spices. Cover and cook on low heat for 4 to 5 hours, or until the chicken becomes exceptionally tender. If needed, the slow cooker can remain on the warm setting for up to 3 additional hours.

Prepare the Honey Mixture

While the chicken cooks, combine the honey with the remaining 1 teaspoon of red-pepper flakes and ½ teaspoon of garlic powder in a small bowl or liquid measuring cup. Cover the mixture and let it rest at room temperature until it is ready to use.

Shred and Season the Chicken

Once the chicken has finished cooking, use two forks to shred it finely, ensuring it is well-mixed with the cooking liquid. Add the spiced honey and cider vinegar, then toss the mixture thoroughly to coat. Taste and adjust the seasoning with additional salt, red-pepper flakes, or vinegar as desired to enhance the flavor balance.

Prepare the Slaw

In a medium bowl, combine the shredded green cabbage, mayonnaise, scallions, and lemon juice. Mix well and season with salt and black pepper to taste. For optimal freshness, prepare this step close to serving time.

Assemble the Sandwiches

Lightly toast the buns, then spread them with mayonnaise. Add a few shakes of vinegary hot sauce for an extra kick. Pile the shredded chicken onto the bottom halves of the buns, then top generously with the prepared slaw. Place the top buns and serve immediately.