Blackberry, Peach and Oat Cobbler

Think of pairing fruit in recipes like planning a seating chart at a dinner party. It’s usually a good idea to split up your two anarchist teenage nephews, right? Similarly, in a crumble it’s best to avoid putting two tart berries, like blackberries and cranberries, in the same bowl. For this recipe, I partner the testy blackberry with a dose of mellow peach, whose sweet charms keep the party on an even keel. Also, blackberries tend to lose their structure under heat, while the peaches—like apples and pears—stay true to form and give your crumble hearty body.