be onto a good thing

be on to a good thing

slang To be in a favorable or enjoyable situation. I think I'm on to a good thing with my new job because I can work from home as much as I want. Your new boyfriend seems really sweet—I think you two are onto a good thing.
See also: good, on, thing

be onto a good ˈthing

be in a position or situation which brings you a lot of benefits: They’ve offered her a company car and a huge salary. She’s onto a good thing there.
See also: good, thing