My understanding is that UK food was on a par with other European countries in medieval times. By the 1950s to 1970s, it was pretty bad though. No doubt some of this was down to wartime rationing. Perhaps some of it was due to protestant fear of anything too enjoyable.

There is a reason there are thousands of Indian restuarants in England and approximately zero English restaurants in India. ;0)

Thankfully, food has improved vastly in the UK since the 70s.