Marmite is a somewhat polarising spread. (Their slogan is "Love it. Hate it.") Made from brewer's yeast, the salty paste is the British answer to Vegemite. Like Vegemite, it has an umami-packed, almost condensed-soy-sauce-like flavour that can be overwhelming in large amounts. Add just a smidge, though, and you'll boost the savoury-factor of whatever you're eating many times over.