Put the feta cheese in the freezer for 10-odd minutes. During this time, beat the eggs with the vinegar.
Separately, mix the breadcrumbs, ground walnuts, black pepper, basil and oregano. Cut the feta cheese into 4 thick blocks. Heat the oil in a frying pan. Roll the cheese pieces first in the eggs, then in breadcrumbs and eggs again.
The crumbing must cover the cheese thoroughly. Fry the crumbed cheese pieces evenly on both sides. Once nice and golden brown on one side, carefully flip it over to the other.
Put the pieces on a cooking grid with paper towels underneath. Serve the crumbed feta cheese with a walnut crust garnished as desired.