Apple crumble is one of those desserts all cooks should have in their back pockets. It’s a no-fuss favorite that works as well for dessert with a big scoop of ice cream as it does for breakfast with some plain, whole-milk yogurt. This recipe starts with a hefty crumb mixture, studded with pecans and old-fashioned rolled oats. Plenty of butter and sugar ensure the crumb stays crisp after baking, creating a delightful textural contrast between topping and tender fruit. Using a mix of sweet and tart apples that soften at slightly different rates also keeps this recipe interesting.