For dressing, put all ingredients (leaving a few herbs for the salad) in the bowl of a food processor. Blend until well combined.
Step 2
Scatter beans and spinach over a large platter. Arrange cucumber, tomato, mango, onion and radish on top and gently toss together with your hands. To serve, top the salad with the avocado, feta and herbs, and serve the dressing on the side.