Cover peeled potato with hot water, season with salt and boil until ready. Drain the water, dry potato and mash it while hot.
To the potato puree add flour, eggs (reserving a little egg for brushing) and mix well.
To make filling, strain cottage cheese and blend it with egg and sugar.
Put the prepared potato mass on a greased baking tray, shaping 6 balls out of the mass. Make a hollow in the middle of each potato ball and fill it with cottage cheese mass. Brush potato mass with egg, brush cottage mass with sour cream and bake the tartlets in an oven at 445oF (230oC) and serve hot.
