NU
Nubank, a crypto-friendly Brazilian bank owned by Nu Holdings, has proven to be a lucrative investment for Warren Buffett's Berkshire Hathaway, which has seen a 93% gain on its Nubank stock this year, making it the best performer in Berkshire's portfolio. Despite some of Berkshire's other key investments like Coca-Cola and Kraft Heinz showing declines, Nubank has shown significant operational growth, increasing its customer count and revenue substantially, and even transitioning from a net loss to a substantial profit. This performance, along with its close ties to the highly regarded Sequoia Capital, makes Nubank an attractive stock to consider for investment, despite the relatively small size of Berkshire's stake in it compared to its overall portfolio.