Officially, we go to Headhouse Market, which opens for the season in May, for leafy greens and other good-for-you produce. But we’re not averse to slipping a little something sweet into our recycled tote bag. There’s none better to be found there than a canelé (say it “cann-uh-LAY”) from vendor Market Day. Canelés may resemble elongated miniature Bundt cakes, but these elegant pastries are more sophisticated: Their delicate fluted shells break open to reveal velvety, almost custard-like interiors with notes of vanilla, rum and citrus. The cakes, which trace their history back to pre-Revolution France, where — depending on which story you believe — either nuns or dockworkers in Bordeaux invented them, get their irresistibly crunchy exteriors from a mixture of butter and organic beeswax that is brushed into the molds before baking.