Huế has, by any honest count, something like a hundred coffee shops — so when Mr Phong and Mrs Hương decided to open one more, they didn't try to compete on the usual terms. They invented something nobody had made before: coffee built with salt. They kept the recipe to themselves for years. It got out anyway, the way good ideas do, and cà phê muối now sits on menus from Sài Gòn to Singapore — almost none of which know, or say, where it actually came from. The drink is built in three layers: sweetened condensed milk at the base, a salted cream above it, and dark coffee dripped slowly through a phin on top. Stirred together it tastes like salted caramel — though the salt isn't there to be tasted on its own. It pulls sweetness out of the bean in a way sugar alone can't reach, the same trick a pinch of salt plays in a good caramel sauce. This workshop happens at the original café, taught hands-on by the family who thought of it first — not a version of the drink borrowed from somewhere else, but the actual source everyone else has been copying without crediting. Two hours, private or in a small group, learning to build the three layers in the order that makes the trick work.