Yeast Dough

• ¼ ounce dry yeast
• 2 tablespoons plus ½ teaspoon sugar
• 2 teaspoons warm water (about 100 degrees)
• 4 cups (all-purpose) flour
• 1½ teaspoons salt
• 1¾ cups warm milk (95 degrees)
• 3 egg
• 6 tablespoons unsalted butter, melted and cooled to lukewarm

Piroshki Filling

• 8 tablespoons unsalted butter
• 2 medium onions, minced (about 1½ cups)
• 1 pound mushrooms, minced
• 2 hard-boiled eggs, minced
• ¼ cup raw rice, cooked (to make about ½ cup cooked rice)
• 1½ teaspoons salt
• ½ teaspoon freshly ground pepper
• ¼ cup each minced fresh dill and parsley

Egg Wash

• 2 eggs
• 2 tablespoons heavy cream

Procedure

For the dough, stir together the yeast, ½ teaspoon sugar, and the water in a mixing bowl and let stand until bubbly, about 5 minutes. Transfer the yeast mixture to the bowl of an electric mixer and add the 2 tablespoons sugar, 2½ cups of the flour, the salt, and ½ cups of the milk. Use the dough hook to beat 1 minute on low speed. Beat the 3 eggs lightly with a fork to blend and add to the mixer bowl along with the remaining flour and milk. Beat 1 minute on low speed. Increase speed to medium and beat 2 more minutes. Then reduce speed again to low, add the butter and beat 2 minutes more. Finally, turn the mixer to medium-high speed and beat for 10 minutes. (If yours is not a heavy duty mixer, you will need to stop a few times for 2 minutes at a time during this final beating to allow the mixer to cool off.) The dough is ready when it no longer sticks to the side of the bowl.

Cover the dough loosely with a towel and let rise in a warm place until doubled, about 45 minutes; punch down.

Meanwhile, to make the filling, melt the butter in a large sauté pan or skillet over medium heat. Add the minced onions and cook until soft and golden, but not brown, about 10 minutes. Add the mushrooms and cook 5 minutes longer. Remove from the heat and stir in the remaining filling ingredients. Taste and adjust seasonings. Let cool.

Preheat the oven to 375 degrees. To assemble the piroshki, roll out the dough on a lightly floured surface to 1/16 inch thick. Cut out circles of dough with a 2½-inch round pastry cutter. Make the egg wash by beating together the eggs and cream and brush over the edges of the circles. Place 1 heaping tablespoon of filling in the center of each circle. Cover with another circle of dough. Pinch the edges together to seal and place on an oiled baking sheet. Repeat to make all of the piroshki. Let the piroshki rise in a warm place until they are about one quarter again as large, 20 to 30 minutes. Brush the piroshki with the remaining egg wash and bake until golden, 8 to 10 minutes. Or, you may omit the final glazing and deep-fry them in hot peanut oil for about 3 minutes.