3 1/2 cups all purpose flour
3 large eggs
2 tablespoons sour cream, buttermilk, or plain yogurt
1 cup water (more if required)
butter or oil
salt and pepper
3 medium or 2 very large waxy potatoes (baking)
3 T unsalted butter
1-2 T light olive oil (or schmaltz)
1 large onion, minced
2-3 cloves garlic, minced
2 cups cabbage, finely shredded
1 small leek, finely minced (optional)
2 T Parmesan or white cheddar cheese, grated
Combine flour, half of the water, eggs, and the sour cream, buttermilk or yogurt in a large bowl. Stir vigorously to incorporate the eggs.
Slowly stir in the remaining water until a dough begins to form. Turn out onto a floured surface and knead gently, lifting dough to stretch.
Continue lifting and stretching the dough until the dough is smooth and somewhat sticky inside, about 3 minutes or so. Do not overwork the dough - if it begins to become elastic, allow it to rest 5-10 minutes under an overturned bowl before working with it again.
When the dough has been kneaded enough, place in a storage bag in the refrigerator to rest 20 minutes, or leave on the counter under an overturned bowl 30 minutes, to allow any gluten which may have developed to rest.
While the dough is resting, you can prepare the filling.
Cook the potatoes in their jackets, in a covered heavy pot with barely enough water to cover them in slightly salted water (add about 2 tsp salt to the water). Simmer over low heat until potatoes are fork tender, then remove from heat. (If you can judge when they'll be done, remove from heat 10 minutes in advance and just allow to steam in the pot with the heat turned off).
Allow the potatoes to cool sufficiently to handle, and rub off the skins with a clean towel. Drain the pot you cooked them in, and return the potatoes to the pot and shake them around a bit to dry them.
Put the potatoes through a sieve or a potato ricer if you have one, otherwise, use a masher. Set them aside.
In a skillet, combine butter and oil or schmaltz over medium heat to melt. Saute the garlic, onion, and leek, if you have one, for a few minutes until they begin to take on a translucent color.
Stir in the cabbage, turn the heat to high for 1-2 minutes, stirring constantly, reduce heat and allow cabbage to begin to brown, 6-8 minutes. Then add the potatoes, cheese, and season to taste. Remove from heat and go on to work with the dough again as the filling cools.
Remove the dough from the refrigerator and form it into balls 1 1/2 to 2" in diameter. Roll each out with a rolling pin into a 3-3 1/2" round approximately 1/8 inch in thickness. Cover the ones you've made with a damp paper towel as you work. If you prefer, you can use a KitchenAid pasta roller attachment (or other pasta machine) to roll out the dough circles. Be sure to flour both sides lightly first.
Hold the dough in one hand, and place a round ball of filling or spoonful into the center. Fold in half to enclose the filling, and pinch the edges securely together. Don't allow filling to touch the edges to avoid an imperfect seal. Be sure there are no openings along the edges, or the filling will boil out.
Boil a large pot of salted water as you continue to fill the remaining pirogi until all the ingredients run out. As you work, place a sheet of waxed paper dusted lightly with flour or corn meal over and between the pirogi layers until ready to boil.
Cooking: Gently lower pirogi into rapidly boiling water 3-5 at a time and cook for a few minutes until they float to the surface. Remove with a slotted spoon and continue til all are cooked. Serve fresh with melted butter, or saute in butter until lightly brown on outside.
An alternative to cooking these in water is to boil them in the broth remaining from a boiled ham, or in chicken broth.