Some say the best way to marinate fried chicken is in a buttermilk batter, which has acidic components that make the meat tender and flavorful. Unfortunately for those who try to cut calories by "oven-frying," buttermilk doesn't always work. This recipe uses Greek yogurt mixed with mustard, garlic, and seasonings, so that there's not only acid to break down the chicken and make it juicy, but added flavor from the yogurt and mustard.
Whisk together the yogurt, mustard, garlic, 2 teaspoons of the salt, and ½ teaspoon of the black pepper. Add the chicken pieces and turn to coat in marinade. Cover the bowl and refrigerate for at least 30 minutes or up to 12 hours.
Preheat the oven to 425 degrees. Line a rimmed baking sheet with foil. Place a wire rack on top of the baking sheet and lightly coat with nonstick cooking spray.
Place the flour, paprika, thyme, baking powder, remaining 1 teaspoon of salt, and ½ teaspoon of black pepper in a large plastic bag. Remove the chicken from the marinade, shake off excess, and place in the flour mixture. Shake to coat, shake off excess coating, and place on a prepared rack. Repeat with the remaining chicken. Discard the remaining marinade and seasoned coating.
Lightly coat the chicken with cooking spray and bake until golden brown and a digital thermometer inserted into the center of the piece reads 160 degrees, about 50-60 minutes.