i dunno mate. i must admit my british experience was not very long, but still i remember how hard it was to find a good grocery, with (real) fresh vegetables.
i mean, the easiest, simplest thing i can imagine right now is a pasta con la salsa... it requires just a few ingredients and about 20 minutes of cooking....
but still u need fresh parsley, fresh basil (and when i say fresh i mean that the leaves must have been taken from the plant 3 days before tops) decent quality tomatoes onion and and garlic (and when i say onion and garlic i mean the bulbs, not that horrible flavourles grated stuff).
i honestly wasn't able to find any of theese ingredients (in a good state) in southampton..... neither in portsmouth.... neither in ireland.....
my mates told me that those things can actually be found but they are quite rare (and extremely) expensive as the wheater is not exactly appropriate for things like parsley and basil.
in italy such a meal would cost about 1 euro (per person), while in uk even if u'd know where to find fresh parsley, fresh basil, an entire bulb of onion and garlic, and some (real) pasta... it would be much more expensive.
not to mention cheese. parmigiano or grana are so damn expensive in uk
anyhow what i found scary was the tuna-mayo-pepper partnership...
mayonnaise has a very strong flavour and puttting it together with a fish....

however, as i said, in the end it's all about personal taste