Pulse the oats in a blender or food processor. Add the bananas and salt and blend until smooth.
Transfer the batter to a medium bowl. Fold in the raisins.
Spoon one heaping tablespoon (15 mL) of the batter onto the prepared baking sheet, leaving one inch (2.5 cm) between cookies. Repeat with the remaining batter.
Bake until a tester inserted into a cookie or two comes out clean, 15 minutes. Remove the baking sheet from the oven and allow the cookies to cool on the baking sheet for ten minutes before eating.