Try this Mushroom bourekas recipe, or contribute your own.
Why is the phyllo dough tearing halfway through the folding process? Keeping the stack covered with a damp towel prevents the paper-thin sheets from drying out under ambient kitchen air. Defrost frozen dough slowly overnight in the refrigerator to maintain the structural integrity of each individual layer. Working with dry pastry leads to immediate cracking when forming geometric shapes.
Moisture management defines the filling. Two pounds of sliced mushrooms require a full ten to fifteen minutes in a hot pan to release their internal liquid and brown properly. If the onions and fungi retain excess water, the steam will saturate the pastry from the inside out during baking, preventing the desired shatteringly crisp texture at 350 degrees Fahrenheit.
Folding requires precision. Slice the mushrooms large enough to retain meatiness, yet small enough to fit inside the tight triangular parcels without puncturing the delicate edges. Brush each folded layer lightly with a mixture of melted margarine and water to adhere the strata together. Press the corners snugly around the filling so empty pockets do not scorch in the oven.
Baking takes between fifteen and twenty minutes on parchment-lined cookie sheets. Margarine provides a direct dairy-free substitution for butter without altering the browning rate of the pastry. Consume these pastries fresh because residual internal steam softens the crust rapidly during storage, rendering reheating ineffective outside of a dry oven.