Other forms: hot commodities
A hot commodity is someone or something that everyone wants. It flies off the shelves, or their phones won't stop ringing, or her calendar is full.
The use of hot here means "popular or successful." A commodity is something that can be bought or sold, but it's being used a little more broadly here to also to refer to people and entities who might be in demand, whether for pay or not. So, a hot commodity is anything that's super popular, successful, or desired. For example, "He's a hot commodity; everyone wants his advice these days."