MUSHROOMS IN PUFF PASTRY

First knead the dough from the flour, mineral water and a pinch of salt. Roll out a rectangular shape from the dough and coat it with half of the butter or margarine. Roll out the dough by forming a cube and leave it in the freezer for 20 minutes to harden. Roll out the dough into a rectangular shape 1 cm thick. Apply the other half of the margarine or butter and fold the dough back into a cube. Leave for 20 minutes in the freezer to rest. During this time, prepare the mushroom filling. Fry finely chopped onions, fresh mushrooms, garlic and spinach in a pan over low heat. Add salt and mixed dried vegetables. Before removing from the heat, stir constantly for about 8-10 minutes and add the mustard and ground black pepper. Divide the dough into two equal parts and roll them into a rectangular shape as in the photo. On the first part, add the filling that you have previously cooled. Cover with the remaining crust and squeeze the ends with a fork. Before baking, if desired, coat it with beaten egg. Bake this puff pastry for about 20-25 minutes in a preheated oven at 200 degrees. Allow to cool for 5 minutes before serving.