Clean the mushrooms. Personally, I used wild fresh, white and portobello mushrooms. Cut them in slices and leave them aside.
Heat the olive oil over high heat in a low saucepan. Add the olive oil and cook the mushrooms, always over high heat, for 4-5 min, until they absorb their juices. Add the onions and garlic, minced, and saute them until dry, for 3-4 min. Add the tomato (without its juices), salt, pepper and bukovo. Boil the stuffing for a few minutes, until it absorbs its juices.
Bake three pastry leaves so that they absorb the juices and your pie is more tasty. Lay the 2 sheets on 2 baking sheets and bake them in a preheated oven, at 180°C for 10 min, until dry and slightly golden brown. Let them cool down. Break them in uneven pieces.
After the stuffing cools down a little, add the walnuts and sesame, and stir. If you like nutmeg, it goes very well with the mushrooms. Add 2-3 pinches. Otherwise, add a little parsley, minced.
Smear a little olive oil on a 40 cm baking pan and lay the pastry leaves on it, sprinkling in between with a little olive oil.
Add the broken baked leaves. Pour the mushroom stuffing on top.
Fold the leaves spreading over the baking pan over the stuffing. Cover the pie with the last two leaves, oiling them in between. Make sure you lay the leaves making several pleats, creased. Carve the pie on the surface, oil the surface well and sprinkle a little water on top.
Bake in a well preheated oven at 180°C, with extra heat on the oven elements, for 1 hour, until the pie turns golden brown and no longer sticks on the baking pan.