This dessert features two varieties of apples in season: Firm but tender Rome holds its shape, while the creamy McIntosh cooks down into a sauce.
Make crust: In a food processor, pulse flour, sugar, and salt until combined. Add butter; pulse until mixture resembles coarse meal with a few pea-size pieces of butter remaining. Sprinkle with 1 tablespoon ice water. Pulse until dough is crumbly but holds together when squeezed (if necessary, add 1 tablespoon more ice water). Do not overmix. Form dough into a 1-inch-thick disk, wrap tightly in plastic, and refrigerate until firm, at least 1 hour (or up to 2 weeks). On a floured piece of parchment, roll out dough to 1/8-inch thickness. Refrigerate until firm, about 20 minutes.
Make filling: Preheat oven to 375 degrees. In a large bowl, toss together apples, cranberries, brown sugar, lemon juice, flour, and salt. Transfer to a 2-quart baking dish; dot with butter. Tear or cut dough into pieces (around 3 inches square). Lay dough pieces, overlapping slightly, over apple mixture. Brush dough with cream and sprinkle with coarse sugar. Bake until crust is browned and juices are bubbling, about 1 hour. Let cool 15 minutes. Serve warm or at room temperature.