What does ほっと一息 mean? I can tell it's made of the words for "hot" and "breath", and according to Google translator together they either mean "relievedly" (wut) or "hot breath". If I were to hazard a guess it would be the name of the steam that comes out of hot beverages? But I feel like it would be a stretch.

一息: short break / breather
So short break for warm drink, I guess? I'd use coffee break, but that's just weird when Murasame clearly says cocoa...