Paszteciki z Serem i Pieczarkami (Polish Cheese and Mushroom Pastries)

Paszteciki z serem i pieczarkami are a beloved Polish delicacy, perfect as a snack, appetizer, or even a light meal. These savory pastries are filled with a rich blend of sautéed mushrooms and creamy cheese, wrapped in a flaky dough that melts in your mouth. Popular at family gatherings, holidays, or casual get-togethers, they’re versatile and easy to make. Whether you’re familiar with Polish cuisine or looking to try something new, these pastries are sure to impress!

Ingredients
For the Dough:

2 ½ cups all-purpose flour
½ cup unsalted butter (cold, diced)
1 large egg
½ cup sour cream or plain yogurt
1 tsp salt
For the Filling:

2 cups finely chopped mushrooms (e.g., button or cremini)
1 medium onion, finely diced
1 tbsp olive oil or butter
1 cup shredded cheese (e.g., mozzarella, cheddar, or gouda)
½ tsp salt
¼ tsp black pepper
½ tsp dried thyme (optional)
For Assembly:

1 egg (beaten, for brushing)
Sesame seeds or poppy seeds (optional, for garnish)
Directions
Prepare the Dough:

In a large mixing bowl, combine the flour and salt. Add the cold butter and rub it into the flour using your fingers or a pastry cutter until the mixture resembles coarse crumbs.
Add the egg and sour cream, mixing until a dough forms. Wrap the dough in plastic wrap and refrigerate for 30 minutes.
Make the Filling:

Heat the olive oil or butter in a skillet over medium heat. Add the onions and sauté until translucent.
Add the chopped mushrooms, salt, pepper, and thyme (if using). Cook until the mushrooms release their moisture and it evaporates. Remove from heat and let cool.
Once cool, mix in the shredded cheese.
Assemble the Paszteciki:

Preheat your oven to 375°F (190°C) and line a baking sheet with parchment paper.
Roll out the chilled dough on a floured surface to about 1/8-inch thickness. Cut into squares or rectangles, depending on your preference.
Place a spoonful of the filling in the center of each piece of dough. Fold the edges over the filling, sealing tightly. You can use a fork to crimp the edges for a decorative touch.
Bake:

Place the pastries on the prepared baking sheet. Brush each one with the beaten egg and sprinkle with sesame or poppy seeds if desired.
Bake for 20–25 minutes or until golden brown.
Serving and Storage Tips
Serving: Serve warm with a side of sour cream or your favorite dipping sauce. They pair wonderfully with a hot bowl of borscht for a traditional Polish experience.
Storage: Store in an airtight container in the refrigerator for up to 3 days. Reheat in the oven at 350°F (175°C) for 5–7 minutes to restore their crispness.
Variations
Vegetarian Delight: Add spinach to the mushroom mixture for a nutrient boost.
Meaty Twist: Include cooked ground beef or diced ham for a hearty option.
Cheese Variety: Experiment with different cheeses, like blue cheese for a bold flavor or ricotta for a milder taste.
Spicy Kick: Add a pinch of chili flakes to the filling for a touch of heat.