Step 1

Bring 1 lb. fresh or frozen cranberries, 2 Tbsp. unsalted butter, ¾ cup sugar, and 1 tsp. Diamond Crystal or ½ tsp. Morton kosher salt to a simmer in a medium saucepan over medium-high and cook, stirring occasionally and smashing some of the cranberries, until berries have burst, juices are syrupy, and you can see the bottom of the pan when you drag a wooden spoon through, 12–15 minutes. Let sauce cool, then stir in ⅓ cup whole grain mustard.Do ahead: Sauce can be made 3 days ahead. Let cool; cover and chill.

Step 2

Divide 6–8 lb. skin-on, bone-in chicken wings, thighs, and/or drumsticks between two 1-gal. resealable plastic bags. Whisk 2½ cups buttermilk, 2 Tbsp. hot sauce, 2 Tbsp. Diamond Crystal or 1 Tbsp. plus ½ tsp. Morton kosher salt, and 1½ tsp. garlic powder in a large measuring glass or small bowl. Divide marinade between bags, seal, and smoosh to coat chicken. Chill, turning bags occasionally, at least 12 hours and up to 1 day.

Step 3

Whisk 3 cups all-purpose flour, ½ cup potato starch or cornstarch, 2 Tbsp. finely chopped sage, 1 Tbsp. plus 1½ tsp. Diamond Crystal or 2½ tsp. Morton kosher salt, and remaining 1½ tsp. garlic powder in a large bowl. Add 2 Tbsp. dried thyme, crushing between your fingers to break up bigger pieces, and season generously with freshly ground black pepper; whisk again. Drizzle 2 Tbsp. marinade into dredge; work in with a fork (this will help the dredge form clumps, making for crispy, craggy bits on the fried chicken).

Step 4

Working with 1 piece at a time, remove chicken from marinade, letting excess drip back into bag. Transfer to bowl with dredge and toss to coat thoroughly, tapping off excess. Place chicken on a rimmed baking sheet.

Step 5

Pour vegetable oil into a large heavy pot to come 2" up sides; fit with thermometer. Heat oil until thermometer registers 350°. Carefully drop in 4 pieces of chicken and cook, turning occasionally and adjusting heat to keep oil between 300°–325°, until browned and crisp, 10–14 minutes. Using tongs, transfer to a wire rack set inside another rimmed baking sheet; season immediately with salt. Repeat with remaining chicken.

Step 6

Working in 2 batches, add 10 sage leaves to oil (be careful; oil will spatter). Cook until crisp, 30–60 seconds. Using a spider or slotted spoon, transfer to wire rack with chicken; season with salt.

Step 7

Transfer chicken to a platter; top with sage leaves. Serve sauce alongside.