1. Preheat the oven to 325°F. Line a baking sheet with parchment paper.
2. In a large bowl, stir together bananas and coconut oil until smooth. Stir in oats, dried coconut, walnuts, mulberries, vanilla extract, ground cinnamon, and salt.
3. With your hands, roll mixture into 10 balls, and place about 2 inches apart on the prepared baking sheet.
4. flatten cookies until they are about 2 inches in diameter.
5. Bake until cookies are lightly browned and dried, 20 to 25 minutes. Let cookies cool on the baking sheet for a few minutes, then transfer them to a wire rack and let cool completely.