Wash the pork, dry and cut into slices. Finely chop the onion.
Heat the vegetable oil in a deep enough frying pan, put the pork slices and fry on high heat until golden (≈ 5 minutes)
Add onions to the meat, mix, reduce the heat to medium and fry for another 5-7 minutes.
Salt and pepper to taste, pour peppercorns, flour, mix thoroughly and fry for about 3 minutes.
Add ketchup and mix well.
Add bay leaf, pour a glass of water at room temperature. After waiting for the water to boil, cover with a lid, reduce the heat to near minimum and simmer for 30 minutes.
Season the prepared dish with chopped parsley.