One of the best ramen I’ve ever had is this:
https://ramen.haus/united-kingdom/london/cha-mori-ramen-kana...
Pre-Covid, this restaurant would regularly have queues down the street to get in. But it’s a small place. Basically the size of someone’s front room. Definitely worth a visit.
Kanada-Ya is a chain with at least 5 locations in London, and while they're fairly good, they're still somewhat focused on Deliveroo-type transactions.
It remains quite different from a genuine ramen shop in Japan.
That wasn’t the case pre-Covid when I was talking about. But it’s still good even now.
And it’s obviously going to be quite different from Japanese restaurants because London isn’t in Japan (surprise surprise).
For a long time, their first restruant in Covent Garden always had a hell of a queue and tiny seating area.
Shoryu Ramen is good too and bone daddies though they do other stuff too.
London does have a number of independent Ramen spots -- not many though.