Piroshki - cooking recipe

Ingredients

1/2 lb. lean ground beef
1 onion, chopped
1 Tbsp. tomato paste
1 tsp. salt
1/2 c. sour cream
2 Tbsp. milk
1/4 lb. bacon, diced
1/2 lb. mushrooms, chopped
1 tsp. dried thyme leaves
1/2 tsp. black pepper
1 egg
Flaky Butter Pastry (following)

Preparation

Crumble beef and set aside.
In heavy skillet, brown bacon until crisp.
Pour off drippings.
Add onion and beef, saute for 3 to 4 minutes, until meat has lost its pinkness.
Add mushrooms and cook until liquid is absorbed.
Stir in tomato paste, thyme, salt, black pepper and sour cream.
Remove from heat and cool.