With an airy-creamy texture and citrus-bright flavor, this quick dessert captures the essence of an indulgent lemon mousse—but is far lighter than traditional versions. The key is low-fat cottage cheese. Its flavor is similar to cream cheese, and when whipped in a food processor, it becomes creamy and fluffy. Lemon zest and juice offer sunny notes, and crumbled graham crackers provide some crunchy contrast as well as a further nod toward cheesecake. You can make it up to a day ahead, but hold off on the graham cracker crumbs until shortly before serving so they stay crunchy.