The Russian version of pierogies, pirozhki are small turnovers that are baked rather than boiled. Their savory, rich mushroom-and-liver filling packs a big punch within a crisp little pastry.
Cooks' notes:
•Dough can be chilled up to 2 days.
•Filling can be made 2 days ahead and cooled completely, uncovered, then chilled, covered.
•Pirozhki can be assembled (but not baked) and chilled on a baking sheet, covered, up to 1 day or frozen on baking sheet until frozen hard, then gently transferred to a sealed plastic bag and kept, frozen, up to 1 week. Thaw on baking sheet 30 minutes before baking.