Adding the usual amount didn't do much for the flavour but gave it a comforting scent. Similar to vanilla, it didn't hurt the coffee, but it didn't help it much either. Except in the aftertaste where it loitered warmly in seemingly natural harmony with the nutty brew.
A generous pinch to the espresso grind, however, added not only a stronger and more nuanced cinnamon aroma, but also a pronounced, almost spicy, flavour on the front-middle of the palate. It was really nice! It warmed me to the core. The flavours blended really well, emphasizing the nutty qualities of the espresso, I thought.
The addition of milk didn't do anything for me. The flavours were merely diluted. A nice drink, but not what we are looking for. Cinnamon definitely is on the A-list and we'll be experimenting with it again.