Blend butter with sugar, add eggs.

Add sour cream, knead until smooth.

Sift the flour, add to egg - oil mixture + cocoa powder, salt, vanilla. Knead the dough. Depending on the weight of eggs, flour may need a little more. The dough is slightly sticky.

Remove the dough 10 minutes in the freezer, it's time to cook the berries. Wash and dry on a paper towel. Turn on the oven, heating to 170 degrees. Divide the dough into 10 equal balls, put into the refrigerator. One to get it and roll out. Put on Your choice of berries and chocolate pieces, sprinkle a little sugar. To tighten the roll, formed into a bagel. Put the bagels on a parchment or a silicone Mat and priporoshit sugar.

Bake at 170 degrees for 20 minutes, until light blush. The finished rolls to cool slightly.