Flattened thin, crumbed, shallow fried. The whole thing is about thickness — get that right and it is difficult to ruin.
Lay each breast flat and cut horizontally almost all the way through, then open it like a book. Put it between two sheets of baking paper and beat it out with a rolling pin, working from the centre outward.
Five millimetres, evenly. Not four in one place and eight in another — an uneven schnitzel cooks unevenly and no amount of care in the pan will fix it.
Salt and pepper directly onto the flattened breast. Seasoning mixed into the breadcrumb mostly ends up in the oil.
Three shallow trays. Flour first and shake the excess off properly; a thick layer of flour turns to paste under the egg. Egg next, letting it drain. Crumb last.
Press the crumbs on gently. Pressing hard compacts them into a solid sheet that later peels off in one piece, which is the opposite of what you want.
This lets the coating hydrate and grip. It is ten minutes of doing nothing and it roughly halves the amount of crumb that ends up in the pan.
Oil a centimetre deep, 175 °C — a crumb dropped in should sizzle immediately and float. Two to three minutes a side.
Tilt and swirl the pan continuously so hot oil washes over the top surface. That motion is what makes the coating puff away from the meat, which is the whole ambition of a good schnitzel.
Never on paper — the underside steams and goes soft within a minute. A rack over a tray, and salt while the surface is still hot enough to take it.
Butter melted in the emptied pan and poured over, lemon at the table.
Almost always one of three things: the flour was not shaken off and turned to glue, the crumbs were pressed on hard, or the schnitzel went into the pan straight from the crumbing tray without resting.
The fourth possibility is oil that was not hot enough. Below about 160 °C the coating absorbs oil rather than sealing, and it separates from the meat as it goes soggy.