Pre-heat oven to 350F (180C), lightly grease a cookie sheet.
In a medium bowl whisk together the flour and baking powder.
In a large bowl beat the butter and sugars until light and fluffy approximately 5 minutes, then add the egg, banana and vanilla beat to combine. Add the whisked flour mixture a little at a time and combine with a wooden spoon or spatula. Then stir in the chocolate chips and chopped nuts.
Drop by spoonfuls on the prepared cookie sheet. Bake for approximately 12-15 minutes. Enjoy!
Notes
If you wish you could use a stand mixer with the flat beater attachment, just be sure to combine the flour, chocolate chips and nuts on low speed and do not over mix. The cookies should be stored in an airtight container. They can be left out at room temperature (if it isn’t too warm) over night. Longer than that they should be stored in the refrigerator. They will keep for up to a week.Or freeze the completely cooled cookies on a cookie sheet for about 1-2 hours until firm then place in a freezer safe container or bag. They will keep for up to 3 months in the freezer.Thaw the cookies at room temperature.