Get all ingredients ready. Measure flour milk wash and shred lemon slice butter grind walnuts. Warm up milk. Put honey into the lukewarm milk with the yeast to dissolve. Leave it for a couple of minutes until it gets foamy. Meanwhile put flour egg butter and lemon zest into a mixing bowl then pour the milk into it as well. Knead it together evenly. Cover mixing bowl with the dough with a kitchen towel and leave it to rest in a warm place for half an hour. After half an hour take the dough out of the bowl onto a floured surface. Divide it into 3 equal pieces. Make balls out of them. Heat the oven to 350�F / 180�C degrees and get the baking tray ready by putting parchment paper into it. Set 2 pieces of balls aside. Get the third ball and on the floured surface roll it out to the size of the baking tin. Lay the flattened dough into the tray. Divide the apricot jam and the ground walnut into two equal pieces. Spread the first half of the jam on the first layer of the the dough. Sprinkle half of the walnut on top. Repeat the steps: roll out the second ball put it onto the first layer spread jam and sprinkle walnut on top. Finish with rolling out the third ball and place it on top. Poke the top with a fork. It might seem like an unnecessary step but if you miss it out the top layer will be uneven an cracked during baking. Place it into the preheated oven for about half an hour or until the top is golden brown. For the chocolate cover melt chocolate butter and unsweetened cocoa powder in a small pan over steaming water. Spread the chocolate evenly on top of the cake. Let it cool down and cut it into rectangles to serve.