Chestnuts are cooked or baked, peel and clean the inside of brown skin. Once cool, grind in a food combine a grainy paste. chopped leeks, red onions and garlic fry 3-5 minutes in half of the butter, stirring occasionally. Remove them, their place in the pan becomes heated remaining butter with the olive oil. Add minced meat chestnuts and fry 5 minutes, stirring, until they brown. Then mixed with onion mixture. Add thawed and well drained blueberries (some of them leave for decoration), bread crumbs, parsley, thyme and rosemary (can be used in dried form), beaten eggs, peeled, cleaned and grated apples, black pepper and salt to taste. Mix and half of it is poured into a ring shape, covered with baking paper, pressing gently with a spoon to not remain hollow and smoothed. Top distributes the chopped goat feta cheese and cover with the remaining chestnut mixture. Ring bake 40-45 minutes in a preheated oven at 200 ° C until a brown crust. Allow to cool a 5 minutes in the form, and then transferred into a greased baking dish with butter. Allow to stand for 1 hour until completely cool. On the thawed puff pastry with a sharp knife, cut 12 strips (2x20 cm), which rank equal intervals on the ring, as their ends underneath it. Rest of dough are cut leaves or other ornaments, which adhere to the ring with a little beaten yolk. tray covered with foil and leave for 45 minutes in the cold. Then dough ornaments carefully smeared with yolk broken and the ring again put in preheated oven. Bake another 40-45 minutes until the dough rise. If necessary, the end is covered with aluminum foil, so as not to burn. finished ring is removed and transferred to a heated serving plate. Decorate with separated blueberries and fresh rosemary sprigs and serve with a side of steamed vegetables and wine sauce (optional).