Line two square tin with parchment paper and grease them with butter.
Take butter in a saucepan and allow it to melt.
Add sugar to it and allow it to heat till it melts and switch off the flame
Once it cools down a little, add cocoa powder to it.
Then add wheat flour to it.
Next, add baking soda followed by vanilla essence.
Then add eggs one by one and mix the batter.
Mix till everything is incorporated and the batter is smooth.
Now fold in the chopped milk chocolate and mix well.
Pour into the baking tin lined with parchment paper.
Preheat the air fryer to 180°C and bake at the same temperature for 20-25 minutes
Remove from air fryer and cool the Brownie completely in a wire rack and slice them.
Enjoy with ice cream or chocolate sauce or powdered sugar drizzled on the top.