For the Chicken:

1. Marinate the Chicken: In a large bowl or resealable bag, combine chicken pieces with buttermilk and hot sauce (if using). Cover and refrigerate for at least 4 hours or overnight.
2. Prepare the Coating: In a shallow bowl, mix flour, garlic powder, onion powder, paprika, salt, black pepper, and cayenne pepper (if using).
3. Fry the Chicken: Heat 1 inch of vegetable oil in a heavy skillet over medium-high heat to about 350°F (175°C). Remove chicken from buttermilk, dredge in flour mixture, pressing to coat. Fry for 12-15 minutes, flipping halfway, until golden brown and internal temperature reaches 165°F. Drain on a paper towel-lined plate.

For the Summer Potato Salad:

1. Cook the Potatoes: Boil salted water, add potatoes, and cook for 12-15 minutes until tender. Drain and let cool before cutting.
2. Prepare the Dressing: In a large bowl, whisk together mayonnaise, Dijon mustard, apple cider vinegar, olive oil, salt, and pepper.
3. Assemble the Salad: Add potatoes, red onion, celery, and chopped eggs to dressing. Toss gently to combine. Garnish with dill or parsley and paprika if desired.
4. Chill and Serve: Refrigerate for at least 30 minutes before serving.