Trim as much fat as possible from the chicken thighs.
Toss chicken with black pepper and 1/2 teaspoon salt in a large bowl. Cover and chill at least 30 minutes.
Whisk eggs, buttermilk, and hot sauce in a large bowl. Set aside.
Whisk flour and remaining 4 teaspoons salt in another large bowl or pie dish. Set aside.
Fit a Dutch oven with a thermometer; pour in oil to measure 2”. Heat over medium-high heat until thermometer reads 325°.
Organize flour, buttermilk mixture, and chicken into an assembly line. Pat chicken dry before dredging to get maximize crispiness. Working 1 piece at a time, dredge chicken in flour mixture, shaking off excess, then dip in buttermilk mixture, letting excess drip back into bowl. Dredge again in flour mixture and place carefully in oil.
Working in two or so batches and returning oil to 325° between batches, fry chicken, turning occasionally, until outside is deep golden brown and crisp and an instant-read thermometer inserted into thickest part of pieces registers 165°, approx. 9-10 minutes.
Transfer fried chicken pieces to a clean wire rack set inside a baking sheet.
Once all chicken has been fried, let oil cool slightly.
Whisk cayenne, brown sugar, chili powder, garlic powder, and paprika in a medium bowl; then carefully whisk in 1 cup frying oil.
Brush fried chicken with spiced oil. Serve with pickles (see NOTES section below for link to my Homemade Dill Pickles...Easy as 1,2,3). And dig in!