In a blender, combine the tomatoes, stale bread, olive oil, garlic, sherry vinegar, salt, and pepper. Blend on high speed until very smooth, about 1-2 minutes. If the mixture is too thick, add cold water gradually until you reach your desired consistency.

Cover the blended soup and refrigerate for at least 1 hour to let the flavors meld.

Divide the chilled soup among 4 bowls. If using, top each serving with chopped hard-boiled eggs and diced cured ham. Drizzle a little extra olive oil over the top and add a touch of black pepper and parsley if desired.