Chocolate and Tonka Bean Muffins

I think I've mentioned before that I much prefer muffins to cupcakes - I find the icing on cupcakes just too much. We have a lovely shop in town which sells a great range of herbs and spices, particularly difficult to find ones. In France I did a day's cookery course in a local restaurant, and one of the ingredients we used was Tonka beans. If you want to find out more about them: http://www.greatbritishchefs.com/how-to-cook/how-to-cook-with-tonka-beans I'd never heard of them, so was interested to taste their flavour. It's hard to describe - a bit similar to vanilla, but with fruity and spicy elements! You only use a little, as they can be harmful in large quantities, so it's claimed. I bought 3 beans from my local shop. I'm explaining all this, because my lovely friend who owns the tea shop, gave me her recipe for chocolate muffins with Tonka bean. The recipe! 200g sr flour, 1 tspn baking powder, 150g white chocolate, 12 small squares of dark choco...