Whisk 1 cup (125 g) all-purpose flour, ⅔ cup (packed; 143 g) dark brown sugar, ¾ tsp. ground cinnamon, and ⅛ tsp. kosher salt in a medium bowl to combine. Add 8 Tbsp. (1 stick) unsalted butter, cut into ½" pieces and chilled; use your fingers to rub butter into the flour mixture until topping resembles coarse crumbs. Cover with plastic wrap and refrigerate while you prepare the apple filling.

Position a rack in the center of the oven; preheat oven to 375°F.

Scoop cores out of 2 lb. firm, sweet apples (4 or 5 medium-large apples), peeled and halved, and discard cores. Cut apple halves lengthwise into ½"–¾"-thick slices (you should have about 6 cups). Transfer apple slices to an ungreased 8"-square baking dish (preferably ceramic, glass, or enameled cast-iron; avoid aluminum or uncoated cast iron) and spread them out evenly. Drizzle 2–4 Tbsp. water over the apples (less if they’re particularly juicy; more if they’re on the drier side).

Squeeze fistfuls of topping in your hand and scatter across the apples so that you have some bigger lumps and some smaller ones (don’t press down on the topping!). Bake until crumble is browned, the apples are tender when pierced with a knife, and the juices are bubbling, 45–50 minutes. Transfer to a wire rack to cool for 10 minutes. Serve warm, with a scoop of vanilla ice cream, a dollop of whipped cream, or a drizzle of heavy cream (if using). Do Ahead: Apple crumble can be baked, cooled completely, covered, and kept at room temperature for 1 day. Reheat, uncovered, in a 300°–350° oven until heated through (10–15 minutes). Editor’s note: This apple crumble recipe was first printed in November 2013 as “Apple Crisp.” Head this way for more of our best apple desserts →