These are my version of ‘Blueberry Sour Cream Coffee Cake’ from Baked in America. by David Muniz + David Lesniak (the link is to amazon.uk’s this book’s page)
I was surprised to know that people call those cakes ‘coffee cake’ in USA, even there is no coffee in it.
Here, in Belfast, it will be perhaps called a ‘tray-bake’ (and maybe ‘square’ ‘slice’ ‘bite’ ) or just simply a ‘little cake’. As I wrote in Rice Crispy Square, we love tray-bake here, and anything baked in a tray can be tray-bake.
When I tried the original recipe first, somehow, there was a pool of butter on top among crumble mix while it was baking. The result was very buttery, short crumble coating on top of cake.
However, I prefer to cut down a bit of butter, so I reduced the butter ratio, to make it more like usual crumble. It hold crumbly shape better and I like it this way.
Blue berry was nice, but I just didn’t have a packet at home the other day. I had frozen raspberry, so I used it instead. It worked well.