Tonight on the way back to our hotel after our evening meal, we passed Ippudo (一風堂) again and this time I couldn't resist. So I rather meanly sent my brother into Starbucks with his laptop to wait (as he very sensibly didn't want more food) while I popped in for a ramen fix. I went for the つけ麺 (cold noodles served separately from the hot soup). I really loved it, as the soup was so meaty and delicious. Afterwards the staff topped my soup up with thinner bonito soup (to water it down) so I could then drink the remainder of it.
I had the chance to order 1.5x more noodles for the same price (850 yen; about £5.50) but I couldn't manage that this time, having already eaten a meal; next time I will for sure. I've been told there are other branches of Ippudo in among other places Osaka and Kobe, both of which we're due to go in the next couple of days, so it could be sooner rather than later.