1. In a large nonreactive container, mix together buttermilk, 1/4 cup Essence, salt, sugar, and garlic. Add chicken to container, pushing down to immerse in liquid. Cover and transfer container to refrigerator for at least 4 hours and up to 24 hours.

2. In a large resealable plastic bag or a double brown bag, combine flour, remaining 1/4 cup Essence, and cayenne pepper; shake to combine. Working in batches, add chicken pieces to bag and shake to coat. Remove chicken from bag, shaking off excess flour. Place coated chicken on a large wire rack set over a baking sheet. Let stand for 20 minutes.

3. Meanwhile, heat 4 inches of oil over medium-high heat in a medium Dutch-oven or heavy-bottomed saucepan until it reaches 300 degrees on a deep-fry thermometer. Working in batches, add chicken, skin-side down, to pot and cook until golden brown, about 10 minutes. Turn, and continue frying until golden brown on bottom side, 8 to 10 minutes. Transfer chicken to a paper towel-lined plate to drain. Let chicken stand 5 minutes before serving.