Pie "Zebra"

Ingredients: 
For the dough: 
2.5 cups flour 
2 teasp. baking 
2 cups sugar 
5 eggs 
1 cup sour cream 
2 tbsp. l. cocoa powder 
1 tsp. vanilla sugar 
For the glaze: 
150 g dark chocolate 
5 tablespoons. l. milk 
1 tbsp. l. cocoa powder 
100 g shelled walnuts 
Preparation: 
Eggs are poured into a large bowl, add sugar and vanilla sugar with a mixer beat white hot. Still whisking, add the sour cream. Sift flour with baking powder, add the egg-cream in the mixture. Beat with a mixer until smooth. 
Divide the dough into 2 equal parts, one to leave as is, but to the other add cocoa powder and mix with a mixer. 
Round dish lay a parchment. Tablespoon from the center, spread in turn two test until they run out. Put the pie in preheated to 180 ° C oven for 40 minutes. 
Meanwhile, prepare glaze. Chocolate break into small pieces, put in a heatproof bowl and place over a saucepan of boiling water. Cook until the chocolate completely melted. Remove from heat, add the warm milk and cocoa powder, stir until smooth. 
Ready to turn the cake out of shape on a large platter. Let cool. With shovels smear cake on all sides cooked chocolate icing. Writing glaze harden slightly (but not completely). 
Nuts chop with a knife in a large litter, sprinkle cake.