Heat a bit of vegetable oil in a pan, and sauté the onion and garlic. Add the ground beef and mix until the beef is browned evenly.
Add the salt, pepper, tomato paste, whole grain mustard, and chopped parsley to the pan. Mix the ingredients well.
Peel and boil the potatoes, and then mash them with a fork.
Add a pinch of salt, the egg, and the cornmeal to the potatoes. The cornmeal ensures that the mashed potatoes are more firm.
Cut the hard cheese into slices. Take a handful of mashed potatoes and form it into a boat-like shape. Fill with the ground beef mixture, followed by a slice of cheese. Add a bit more potato on top of the cheese so that you can fully enclose the meat and cheese, using your hands to form a "pocket."
Finally, fry your potato pockets in a pot of oil until golden and crispy.
