Levison sold almost half a million dollars' worth of Peekaboo Ice Cream before setting out on the company's biggest venture yet: a trip into the "Shark Tank" on the hunt for an investor.

But it wasn't just any job. The brief stint as an ice cream scooper changed O'Leary's life. The "Shark Tank" investor says the day his boss fired him was the moment he realized he wanted to be an ...