Prepare the pan and air fryer. Line a small, air-fryer-safe baking pan (about 6–7 inches square or a small loaf pan) with parchment, leaving overhang for easy lifting. Lightly spray the parchment. Preheat the air fryer to 320°F (160°C) for 3–4 minutes.

Whisk the dry ingredients. In a medium bowl, whisk flour, baking powder, baking soda, salt, cinnamon, ginger, nutmeg, and cloves until well combined.

Mix the wet ingredients. In a separate bowl, whisk brown sugar, granulated sugar, melted butter, egg, and vanilla until smooth and glossy.

Combine wet and dry. Add the dry mixture into the wet and stir gently. Add milk 1 tablespoon at a time until the batter is thick but spreadable. Do not overmix.

Fold in extras. If using nuts or dried fruit, fold them in just until distributed.

Spread the batter. Pour the batter into the prepared pan and smooth the top. The layer should be about 3/4 to 1 inch thick for even cooking.

Air fry. Place the pan in the air fryer basket. Cook at 320°F (160°C) for 14–18 minutes, or until a toothpick comes out with a few moist crumbs. If the top is browning too quickly, tent lightly with foil.

Cool. Let the bars cool in the pan for 10 minutes, then lift out using the parchment and transfer to a rack to cool completely.

Glaze (optional). Whisk powdered sugar, vanilla, pinch of salt, and milk until smooth and pourable. Drizzle over cooled bars. Let set for 10–15 minutes.

Slice and serve. Cut into squares or bars. Enjoy slightly warm or at room temperature.