MARMITE!!!
Perhaps it's because I live in a country that's a former British colony and us ex-subjects have long memories.
But Marmite ppl, seriously, one of the better Brit inventions. Perhaps the only British contribution to my diet.
Try Marmite on toast - that's classic. Or Marmite on a wholewheat bagel. Even better with a slice of melted Emmenthal.