Peel and coarsely grate the potatoes, cut the onions into thin rings.
Mix potatoes, onions and eggs and season heartily with plenty of pepper and a little salt. Fill into a gratin dish. Non-vegetarians can add cubes or possibly bacon slices on top.
Bake in a heated oven at 200 °C for half an hour.
Serve with apple compote.
Our tip: Use bacon with a fine, smoky note!