We started with heavy cream and added buttermilk, modeled after the crème fraîche from Maximum Flavor. Then we added the zest of 2 limes and stirred everything together. We put the lid on and now have it sitting on the counter outside the workshop. By tomorrow we should have a lime-scented, lacticly tangy, thick cream. Then we begin the exploration of where to take it: ice cream, butter, as a sauce for oysters, or as the base for a cheesecake. The possibilities are endless.