Is it too late to buy after it doubled last year? Nu Holdings (NU -2.12%) is a Brazil-based company that's on investors' radars because it's in the Berkshire Hathaway portfolio. It's a tiny percentage of the whole equity portfolio, accounting for only 0.3%, but it packs a strong punch as one of its only true growth stocks. Is it right for the individual investor's portfolio? Nu is reporting extraordinary results Nu is a digital bank that operates in Brazil, Mexico, and Colombia, and it has demonstrated incr ...