Ep. 270. What should one do with a ברכה after they left their apartment (e.g. into a public staircase, hallway, or somebody else's apartment), and now came back and wants to continue eating or drinking.

What should one do with a ברכה after they left their apartment (e.g. into a public staircase, hallway, or somebody else's apartment), and now came back and wants to continue eating or drinking.