Clean the celery. Cut into slices about 1/2 cm thick, peel and briefly rinse. Pre-cook slices in boiling salted water with juice of one lemon for about 5 minutes. Drain and cool a little.
Stir pepper, vinegar, salt and sugar, add 2-3 tbsp. oil. Peel the onion. Rinse tomatoes, quarter and remove seeds. Finely dice both. Clean and rinse lettuce. Mix prepared lettuce ingredients and marinade.
Cut cheese into 4 slices. Mix eggs, season with pepper. Place 1 slice each of ham and cheese between 2 slices of celery.
Turn first in flour, then in egg, and finally in sesame seeds to the other side. Press breadcrumbs well until smooth. Heat 2-3 tbsp oil in a coated frying pan. Fry “Cordon bleu” in it over medium heat for 3-4 min per side. Serve with lettuce. Serve with mashed potatoes.
Tip: Use your favorite ham – then your dish tastes twice as good!