Pre-heat the oven to 180°C (fan)/200°C/400°F/gas mark 6.
Line two baking trays with greaseproof paper.
Place all the ingredients (tin of black beans, 100g oats, 2 ripe bananas, 1 chopped cooked beetroot, 8 chopped dates, 1 teaspoon baking powder, 1 teaspoon vanilla extract and 1 tablespoon cacao or cocoa powder) in a food processor.
Pulse until well combined, pausing once or twice to scrape the sides down.
Using two spoons (as it's quite a sticky mixture) place eight spoonfuls of the mixture on each baking tray, leaving a gap between them.
Flatten with the back of a fork.
Bake in the pre-heated oven for 15-18 minutes until set and slightly crispy on top.
Remove from the oven and allow to cool slightly on a wire rack.
Delicious warm or cold.
Store for a day or two in an airtight container.