First, preheat your oven to 425°F (220°C). While it heats up, whisk together the flour, baking powder, salt, and sugar in a large mixing bowl.
Next, take your cold butter and cut it into the dry ingredients. You can use a grater for ease. The mixture should look like coarse sand. Slowly pour in your buttermilk while stirring until the dough starts to come together. Do not overmix.
Transfer the dough to a floured surface. Gently fold it several times to create layers, then roll it out. Use a biscuit cutter to create 6-7 rounds and place them in a buttered skillet or on a lined baking tray. Bake for 15-20 minutes, or until golden brown. Once baked, brush your biscuits with honey butter while still warm.
Combine softened salted butter with honey in a bowl. Whisk until fully blended and creamy. You can refrigerate it for a thicker texture or use it immediately.
While the biscuits are baking, prepare your chicken in the air fryer. Cook one piece per sandwich at 400°F for 10-12 minutes, flipping midway, until crispy and golden.
Slice the biscuit in half, spread a generous layer of the honey butter on both sides, place the fried chicken breast in the middle, and drizzle with hot honey if desired. Pop on the top biscuit and serve while warm.