Potato Bourekas with Mushroom Sauce

Every bite is satisfying and delicious!

Kosher. Can be Pareve or Dairy, Vegan too.

In a pot of salted boiling water, cook the cubed potatoes until tender. Drain.
Add olive oil to the cooked potatoes and mash them until smooth. You can use a potato masher or fork for this step.
Season with salt and pepper, mix well to incorporate the flavors. Set aside to cool. The filling should be completely cooled before assembling the Bourekas.

Preheat oven to 400°F/200°C.
Use a rolling pin to roll the puff pastry sheets on a lightly floured surface.
Lay the puff pastry sheets flat and cut each sheet into equal-sized squares, about 4ʺx4ʺ (8×8 cm) large.
Mix the egg with a tablespoon of water.
Use a pastry brush to brush a light layer of the egg wash over the edges of each square.
Place one generous tablespoon of the potato filling in the center of each dough square.
Fold them into rectangles (or triangles). Using a fork, pinch firmly along the outer open edge of the triangles to seal.
Set the Bourekas on a parchment paper-lined baking sheet pan.
Brush the tops with the egg wash.
Sprinkle sesame seeds.
Bake the Bourekas until they are puffed and golden for 20-25 minutes.

Heat olive oil in a skillet over medium-high heat. Add chopped onion and cook until golden brown - takes about 5 to 7 minutes.
Add mushrooms and cook until golden brown, stirring occasionally.
Add garlic, sugar, salt, and pepper, and stir well.
In a small bowl, whisk water or broth with cornstarch. Continue whisking until the cornstarch is fully dissolved and no lumps remain.
Slowly pour the cornflour mixture into the pan- it will sizzle! Stir, scraping the bottom of the skillet, for 1 minute or until mostly evaporated.
Lower heat to medium so the sauce is simmering.
Simmer for 2 - 3 minutes until it thickens. It shouldn't be super thick, this is a rich sauce.
Remove from stove.
Serve warm over the Bourekas.