01 -
Set oven to 375°F (190°C) and allow to preheat.
02 -
In a skillet over medium heat, cook onion and garlic until translucent, about 2-3 minutes.
03 -
Add chopped mushrooms to the skillet and sauté until softened, around 4-5 minutes.
04 -
Incorporate fresh spinach and cook until wilted, around 2 minutes. Season with salt and black pepper.
05 -
Remove skillet from heat and allow mixture to cool slightly. Stir in grated cheese and cream cheese until well blended.
06 -
Roll out thawed puff pastry on a lightly floured surface and cut into 24 equal squares.
07 -
Place 1 teaspoon of prepared filling in the center of each pastry square.
08 -
Fold pastry over filling to form triangles or rectangles, pressing edges firmly to seal.
09 -
Brush tops with beaten egg for a glossy, golden finish.
10 -
Place assembled pastries on a baking sheet lined with parchment paper, spacing evenly.
11 -
Bake in the preheated oven for 20 to 25 minutes, or until pastries are golden and puffed.
12 -
Transfer pastries to a cooling rack and allow to cool for 10 minutes before serving.