Fry finely chopped fillet until golden brown (salt to taste).
Add 1 onion cut into small pieces and sprinkle with flour after light frying.
At this time, cut out the core from the bun and chop the parsley.
In a bowl, mix the fillet, sour cream, onion, parsley.
Fill the bun with the resulting mixture and top with three cheese. We put it in the oven for 10-15 minutes at 170-200 ° C (the last 5 minutes I turned on the grill mode).
Delicious breakfast is ready. Bon appetit!