Ingredients

• 6 tablespoons (3/4 stick) unsalted butter, cut into 1/2" cubes
• 1/4 cup vegetable shortening or lard
• 4 cups all-purpose flour plus more
• 2 tablespoons sugar
• 2 tablespoons baking powder
• 2 teaspoons baking soda
• 2 teaspoons kosher salt
• 1 teaspoon freshly ground black pepper
• 1 3/4 cups buttermilk
• 1 1/2 cups buttermilk
• 1 tablespoon chopped fresh dill
• 3 1/2 teaspoons kosher salt, divided
• 1 3/4 teaspoons freshly ground black pepper, divided
• Large pinch of cayenne pepper
• 10 small boneless, skin-on chicken thighs
• Vegetable oil (for frying)
• 1 cup all-purpose flour
• 6 tablespoons peanut oil
• 1 large egg
• 1 tablespoon baking powder
• 1 1/4 teaspoons cayenne pepper
• 1/2 teaspoon garlic powder
• 1/2 teaspoon onion powder
• 10 slices cheddar (optional)
• Sausage Gravy (optional)
• Special equipment: A 3" biscuit cutter

Instructions

1. Preheat oven to 400°F. Place butter and shortening in freezer for 10 minutes.
2. Blend 4 cups flour and next 5 ingredients in a food processor. Add butter and shortening. Pulse mixture until it resembles coarse meal, 20-25 pulses. Transfer mixture to a large bowl. Gradually add buttermilk while tossing mixture with a fork (mixture will not be completely incorporated). Knead in bowl with lightly floured hands just until dough forms, about 3 turns.
3. Transfer dough to a lightly floured surface. Pat out dough until 1" thick. Lift 1 side and fold it over. Gently repeat 5 more times. Roll dough to 3/4"-thick round. Using a 3" biscuit cutter, cut biscuits from dough. Gather scraps and repeat patting out and cutting biscuits for a total of 10 biscuits.
4. Place biscuits on a parchment paper- lined baking sheet, spaced 1"-2" apart. Bake until golden brown and a tester inserted horizontally comes out clean, 12-15 minutes. Transfer biscuits to a wire rack; let cool slightly. Serve warm or at room temperature. DO AHEAD: Can be made 8 hours ahead. Let cool completely. Store airtight at room temperature. Rewarm before serving.
5. For fried chicken: Whisk buttermilk, dill, 1 1/2 teaspoons salt, 1 teaspoon pepper, and cayenne in a large bowl. Add chicken; turn to coat. Cover; chill at least 3 hours or overnight. Pour vegetable oil in a large pot to a depth of 2". Attach a deep-fry thermometer to side of pot. Heat oil over medium heat to 350°F. Whisk 1 1/4 cups water with remaining 2 teaspoons salt, remaining 3/4 teaspoon pepper, flour, and next 6 ingredients in a large bowl. Drain chicken well; pat dry with paper towels. Working in batches, dip chicken into batter. Fry chicken, turning occasionally, until skin is crispy and golden brown and chicken is just cooked through, 9-12 minutes per batch. Drain chicken on paper towels. Split biscuits in half; place 1 bottom half on each plate. Top each with a cheese slice, if desired, then a chicken thigh. Spoon Sausage Gravy over chicken, if desired. Place biscuit top over.
6. Whisk buttermilk, dill, 1 1/2 teaspoons salt, 1 teaspoon pepper, and cayenne in a large bowl. Add chicken; turn to coat. Cover; chill at least 3 hours or overnight.
7. Pour vegetable oil in a large pot to a depth of 2". Attach a deep-fry thermometer to side of pot. Heat oil over medium heat to 350°F.
8. Whisk 1 1/4 cups water with remaining 2 teaspoons salt, remaining 3/4 teaspoon pepper, flour, and next 6 ingredients in a large bowl. Drain chicken well; pat dry with paper towels. Working in batches, dip chicken into batter. Fry chicken, turning occasionally, until skin is crispy and golden brown and chicken is just cooked through, 9-12 minutes per batch. Drain chicken on paper towels.
9. Split biscuits in half; place 1 bottom half on each plate. Top each with a cheese slice, if desired, then a chicken thigh. Spoon Sausage Gravy over chicken, if desired. Place biscuit top over.