In a large bowl, combine the 1.5 cups buttermilk, 1 tbsp hot sauce, 1 tsp smoked paprika, 1 tsp garlic powder, 1/2 tsp black pepper, and 1 tsp salt. Whisk well to combine.

Add the chicken thigh pieces to the buttermilk mixture, ensuring all pieces are submerged. Cover the bowl and refrigerate for at least 1 hour, or preferably 4-8 hours (or overnight) for best flavor and tenderness. The longer, the better!

In a large mixing bowl, whisk together the 2 cups all-purpose flour, 2 tbsp granulated sugar, 2 tsp baking powder, 1 tsp baking soda, and 1/2 tsp salt.

In a separate medium bowl, whisk together the 2 large eggs, 2 cups buttermilk, 1/2 cup melted butter, and 1 tsp vanilla extract.

Pour the wet ingredients into the dry ingredients. Mix with a whisk or spoon until just combined. A few lumps are okay; do not overmix, as this can lead to tough waffles. Let the batter rest at room temperature for 10-15 minutes while you prepare the chicken.

Preheat your air fryer to 375°F (190°C).

In a shallow dish or large Ziploc bag, combine the 1.5 cups all-purpose flour, 1/4 cup cornstarch, 1 tbsp onion powder, 1 tsp cayenne pepper, 1 tsp dried thyme, 1 tsp salt, and 1/2 tsp black pepper. Mix thoroughly.

Remove chicken pieces from the buttermilk marinade, allowing excess to drip off. Do not pat dry. Dredge each chicken piece generously in the seasoned flour mixture, pressing to ensure it's fully coated. Shake off any excess.

Lightly spray the bottom of your air fryer basket with cooking spray. Place chicken pieces in a single layer in the air fryer basket, ensuring not to overcrowd (you will likely need to cook in 2-3 batches). Lightly spray the tops of the chicken pieces with cooking spray.

Air fry for 12-15 minutes, flipping halfway through, until chicken is golden brown, crispy, and cooked through (internal temperature reaches 165°F / 74°C). Repeat with remaining chicken batches.

Once cooked, transfer the crispy chicken to a wire rack to keep it warm and allow any excess oil to drain.

While the chicken is air frying, preheat your waffle iron according to the manufacturer's instructions. Lightly grease the waffle iron plates with cooking spray or melted butter, if necessary.

Pour about 1/2 to 3/4 cup of waffle batter onto the hot waffle iron (or the amount specified by your waffle maker). Close the lid and cook for 3-5 minutes, or until golden brown and crispy.

Remove the cooked waffle and place it on a wire rack in a warm oven (around 200°F / 93°C) to keep warm while you cook the remaining waffles.

Serve the crispy air-fried chicken immediately alongside the warm, fluffy waffles. Top generously with maple syrup and a pat of softened butter. Enjoy!