For the Dressing: Place all the ingredients in a jar or screw-top bottle and set aside for 30 minutes to allow the flavours to infuse.
To Make the Pitta Croutes: Preheat the oven to 200C, 180C for a Fan assisted oven, or 400F or Gas 6. Line a baking tray with parchment paper. Combine the cubes of pitta with the olive oil, mix well and season well with salt. Lay the croutons in a flat layer along the line baking tray. Bake for 10-12 minutes until crisp.
For The Salad: Combine all the salad ingredients in a bowl without the radish. Toss with the dressing and half the croutons, then spoon into a serving dish. Top with remaining croutons and sliced radishes.