This concoction is a brew made by smooshing fresh coffee in a blender with grass-fed, unsalted butter and oil. It was invented by Silicon Valley entrepreneur Dave Asprey, who created the recipe after feeling energized from drinking tea with yak butter (seriously) while meditating in Nepal. Is Bulletproof just a bunch of bull? Angela Dowden, an award-winning nutrition and health writer, isn't terribly impressed.
