Take a microproof mug and put melted butter, condense milk and mix it well
Now add all the ingredients (all purpose flour, baking powder, baking soda, powdered sugar, pineapple essence, milk, chopped pineapple) and mix till the mixture becomes smooth.
Now put the mug in microwave on high temperature for 11/2 minute.
Last decorate the mug cake as per your wish or Serve Pineapple mug cake immediately once baked.