The phrase "hottest thing" means something that is extremely popular, trendy, or in high demand at a given time.
Sentences with «hottest thing»
Sure, editors spend all their time reading and making decisions about what's the next hot thing in fiction. (sarracannon.com)
Just because it's the latest, hottest thing on the market, doesn't mean it is the right one for your business. (rismedia.com)
Imagine being able to buy into the winning group of the moment, ride it higher, and then jump to the next hot thing in a timely fashion. (moneysense.ca)