Dissolve the coffee powder in 1 tablespoon hot milk.
Cream the butter and sugar.
Add coffee and milk mixture
Add the pureed banana.
Add whole wheat flour and make a soft dough, it might be slightly sticky.
Add half the choco chip, mix well.
Refrigerate it for 30 minutes.
Make small cookies stud it with rest of the choco chip and bake in a pre heated oven 180 degrees for 15-20 minutes.
Cool completely and store in airtight container.