Preheat oven to 325 degrees. In a large mixing bowl, mash a very ripe banana with a fork. Add the pumpkin purée, flour and 1 Tablespoon water. Mix well.
Dust your workspace with 1 Tablespoon of the whole wheat flour and place the dog biscuit dough on top and knead 8-10 times. You can add 1 Tablespoon of water if the dough is too dry.
Line a cookie sheet with parchment paper.
Use a rolling pin to roll the dough out to about 1/4 in thickness. Cut into cute dog bone shapes with your cookie cutter and place on the lined cookie sheet.
Bake for 20 minutes. Cool on a wire rack.
Store in an airtight container for up to 10 days.