Preheat over to 350 degrees. Lightly coat two cookie sheets with cooking spray; set aside. In a large bowl, stir together banana, peanut butter, honey and vanilla. In a small bowl, combine oats, flour, milk powder, cinnamon and baking soda. Stir the oat mixture into the banana mixture until combined. Stir in dried cranberries. Using a 1/4 cup measure, drop mounds of dough 3 inches apart on prepared baking sheets. With a thin metal or small plastic spatula dipped in water, flatten and spread each mound of dough to a 2 3/4 inch round, about 1/2 inch thick. Once baked, each cookie will be about 3 1/2 to 4 inches in diameter. Bake, one sheet at a time, for 14 to 16 minutes or until browned. Transfer to wire racks to cool completely. Store in an airtight container or resealable plastic bag for up to 3 days or freeze for up to 2 months, thaw before serving.