Clean and peel the cucumber, remove seeds if necessary and dice it. Peel onions, cut into fine rings. Clean, wash and cut salads into strips. Mix vinegar, salt, pepper and some sugar.
Fold 4 tablespoons of oil underneath. Mix salad ingredients and vinaigrette.
Clean and wash spring onions and cut into fine rings. Dab feta dry. Cut each piece into quarters and halve it horizontally. Turn the feta in flour, tap off.
Brush a large coated pan with oil and heat it strongly. Fry half the feta in it on each side for about 1 minute until the cheese has a golden brown crust, remove. Clean the pan if necessary, oil it again, heat it up and fry the remaining cheese in the same way.
Quarter the lemon. Sprinkle hot feta with spring onions and sprinkle with 2 tbsp. oil. Squeeze lemon quarters over it. Add the salad. Serve with flatbread.