This is a traditional Hungarian recipe that I prepared frequently during my college years. It's poor people's food, but very delicious. The potatoes have to be riced to ensure a perfect creamy texture. The cheese has to be a flavorful, low-fat type. The same dough can also be used filled with jam. My grandmother used to make huge panfuls of these, and we would eat them in no time. They are best fresh, but can be frozen as well.
750 g flour
1 egg + egg wash
5 medium Russet potatoes
125 g butter
0.5 cup milk
2 tsp yeast
2 tbsp water
0.5 tsp sugar
1.5 tsp salt
1/3 cup sour cream
Peel and cook the potatoes in salty water. Press through a potato ricer.
Mix the potatoes with the flour and salt. Bloom the yeast with the sugar in the water. Mix in the room temperature egg. Pour onto the potato mix.
Add the warm milk and the room-temperature sour cream. Knead until supple dough forms.
Roll out on a well-floured surface to 1-inch thick. Criss-cross the top with a knife. Cut circles with a 2-inch cookie cutter. Place onto baking sheet. Brush with egg wash and allow to rise for 40 minutes. If desired, sprinkle with grated Parmesan.
Bake in a preheated 400F oven until light brown. Cool on a cookie rack.