Mary Berry's Jaffa Cakes

It is so annoying when you can't find out for certain how some of the recipes are actually done.  Yes, you can always find out some of it...but, the fine details....not always.

Like, ..... how on earth do you get the chocolate on the top to look like Mary's?  It doesn't tell you other than to say you can spoon it on if you don't want to go to the trouble of getting it perfect.  Huh? Why the heck doesn't she say how she does it and let me make up my mind later as to whether I will do it her way or not?

Here is a pic of hers.... from the Great British Bake Off show... see how lovely the chocolate line is all around the little cake.  Note the great criss cross pattern they say should be there ... I've never seen a store bought version so don't really know what one should look like.    

To me, they almost look like they have been dipped in the chocolate...but, it hardly seems possible as the cake is quite flat and how would you grab the bottom and keep your fingers out of the chocolate? ..maybe a couple of skewers through the bottom of the cake? .. some other method? .. who knows?......  ...... anybody got any suggestions?                                                                  

Then, there are dozens of folks who have made them and put them out there ... and, most of them look like this.  I would probably be too embarrassed to show mine if they looked like this... but, I might.... just to let you know how difficult they were to get right.  There has to be a better way to get the chocolate on there and make it look tidy at the very least. 

I want to try Jaffa cakes some day soon... and want them to look nice.