Matjip

A years-long unemployed 'Ju In-Geong', lies to his former classmates at a reunion, claiming he’s a restaurant owner after being provoked by a friend. Determined not to be humiliated, he decides to actually become a real restaurant owner.
Struggling to manage a nearly empty eatery, he unexpectedly receives a mysterious seasoning from a foreign laborer living upstairs. Overnight, his restaurant becomes packed with customers, transforming him into a true restaurant owner.
However, the happiness that seemed endless doesn’t last long, as he soon discovers the shocking truth behind the seasoning…

(Source: Naver, translated)