Jeppson's Malört is gearing up for its biggest ad campaign yet under current ownership as demand for its unusual flavor grows beyond the Chicago area.

Not so long ago, it was tough to find Jeppson's Malört in bars or liquor stores outside of Chicago and its suburbs. Now, it is in 37 states and counting, thanks to a strange strategy: playing up how disgusting it tastes.

The spirit quadrupled sales by embracing its reputation. A new marketing campaign beginning this month will prompt consumers to share their harrowing tales of trying the extremely bitter Malört for the first time—and to taste it if they haven't before.

Last year, a campaign called "Malört Tastes Like" featured consumer comparisons to "fermented back sweat" and "moist dumpster residue," turning revulsion into a rallying cry for the Chicago-born liqueur.