Have you noticed lately how chocolate is like a limbo contest? The “how low can you go” thing in cacao, however, is sugar content in bittersweet. I like a nice 70 percent bar, of course, but if you really want to earn your purist stripes, I suggest eating cacao nibs, pieces of cacao beans that are roasted and slightly crushed but otherwise unprocessed—Scharffen Berger (www.scharffenberger.com) sells them by the can, and they’re relatively easy to find. They’re crunchy, dark chocolaty and not sweet at all. I like them in cookies (like meringues), sprinkled on vanilla ice cream, and occasionally plain—and it occurs to me that you could make a fantastic brittle with them (if you’re the holiday candy-making sort). Last weekend, I threw a couple handfuls into trail mix, along with dried cranberries and apricots, walnuts, almonds, and some plain granola—low-sugar, in the chocolate arena at least, but energizing enough to scale the highs on a hike.