The day before, peel and finely chop the onion and garlic. Sauté both in 2 tbsp. hot oil. Sweat tomato paste and 1-2 tsp. paprika powder briefly. Stir in tomato juice. Season to taste with salt, pepper and a little sugar.
Bring to the boil and simmer for about 5 minutes. Let the soup cool down and put it in the refrigerator overnight.
The next day, wash the cucumber and peel it if necessary. Halve lengthwise, remove seeds and dice finely. Crumble the feta. Wash and chop parsley. Dice the rolls and roast them in hot butter, take them out. Season to taste gazpacho.
Serve with cucumber, croutons, feta and parsley. Drizzle 1 tablespoon of oil over it.