Peel the cucumbers, deseed the capsicum, peel the garlic and toast the walnuts lightly on a pan on low heat. Reserve a few pieces of walnuts and 1 tablespoon of olive oil, for the garnish.
Remove the crusts from the bread for the soup. The original recipe calls for stale bread, and I have used bread that was about 4 days old.
Dice all the vegetables to make them easier to blend.
Add all the ingredients except for the water, salt, pepper and the ice cubes, into the blender and puree the soup.
Crush about half the the ice cubes and add. Reserve the balance ice cubes.
Add water in small quantities during the blending, till the required consistency is achieved. I like to retain a few small chunks of walnuts and peppers in the soup, but you could make it totally smooth if you wish.
Add salt and pepper, puree again, check for taste and adjust the seasoning.
Add the remaining ice cubes, crushed, and blend again briefly.
Serve cold, with the croutons and with a drizzle of olive oil on top.
If not serving immediately, keep the soup to chill in the fridge and crush and add the reserved ice shortly before serving.