A true Brit never just has "a cup of tea" - it's always either "a nice cup of tea" or "a lovely cup of tea". For those of you who are not British, here is an example of this usage.
B has suffered some sort of crisis - this could be anything from having to get out of bed before 6:00 in the morning to witnessing her entire home blowing up in a gas explosion.
A says, "Would you like a nice cup of tea, dear?"
B takes the nice cup of tea, sips it and says, with a contented sigh, "Ooooh, that's a lovely cup of tea."
My lovely cup of tea this morning is an English Breakfast blend. At teatime I prefer Earl Grey. I also have Assam, Darjeeling, Ceylon and plain Yorkshire tea in my cupboard at the moment.