Preheat the oven to 320°F (160°C) with convection, or 350°F (180°C) conventional.

Remove the potato skins, and peel the eggs.

Butter or oil an ovenproof dish.

For the very bottom of the first layer, add one third of the potatoes. Cut the potatoes into about 1/4-inch (1/2 cm) slices, and lay the slices on the bottom of the dish. It doesn’t have to be just one layer; the potato slices can overlap. Salt the potato layer.

Next comes half of the egg. Using an egg slicer or a knife, slice it into rounds that are also about 1/4 inch (1/2 cm) thick, and place the slices on the potatoes. Salt this layer too.

Next comes half of the sausage. Cover the whole thing with 1/8-inch (2–3 mm) sausage rounds.

Repeat the same thing in one more layer: one third of the potatoes, salted; the remaining half of the eggs, also salted; then the remaining half of the sausage. Put the remaining third of the potatoes on top, and salt this layer as well.

Finally, spread the sour cream over the top.It’s easier to spread if you mix it thoroughly first.

Put the whole thing in the oven, and bake for 1 hour.

The simple layered potato casserole is ready. The dish is very hot, so handle it carefully. You can serve it right away, but it’s excellent reheated too, and it also freezes well. Offer fresh sour cream with it!