This version of the classic chilled soup is from Madrid.
Soak bread in ice water for 10 minutes. Remove crust and discard; squeeze out water from bread.
Puree bread, vegetables, and garlic with water in a food processor or blender. Transfer to a bowl and whisk in lemon juice, vinegar, paprika, salt, and mayonnaise. Chill, then serve garnished with diced cucumbers, peppers, and onions.