Authentic Mexican crema is a mildly tangy cultured cream that is thick yet pourable and the perfect accompaniment to Mexican dishes. Unfortunately, it can be difficult to find and culturing your own can take hours or days. So, to get that flavor profile in a pinch, I utilize cultured milk products that I already have on hand. For a milder flavor, use cream instead of kefir or buttermilk, but for optimal tanginess use kefir. For a little heat, add the jalapeno brining liquid.