How to Make It
In a large bowl, mix the flour, salt and sugar. Using a pastry blender, 2 knives or your fingers, cut in half of the butter until the mixture resembles coarse cornmeal with particles the size of peas. Then cut in the remaining butter until it forms chunks the size of peas. Stir in the ice water with a fork. The dough should hold together when pressed; if it doesn't, add a few more drops of ice water. Pat the dough into a disk, wrap and refrigerate for at least 30 minutes or overnight.
On a large sheet of parchment paper lightly dusted with flour, roll out the dough into a round about 14 inches in diameter; it doesn't have to be perfect around the edges—its roughness is part of its charm. Lay it on a large baking sheet or pizza pan and refrigerate.
Preheat the oven to 400°. In a small bowl, mix together the sugar and cinnamon. Mix 1 tablespoon of the cinnamon-sugar with the flour and sprinkle this mixture over a 9-inch area of the pastry. Spread the gooseberries on top. Reserve 1 1/2 tablespoons of the cinnamon-sugar and sprinkle the remainder over the gooseberries. Fold the edges of the pastry up over the berries to form a 9-inch free-form tart, making pleats and pressing them together lightly. Brush the pastry with water and sprinkle with the reserved cinnamon-sugar.
Bake the tart in the center of the oven for 40 to 50 minutes, or until the gooseberries are bubbling and lightly browned and the pastry has caramelized in spots and is well browned on the bottom. Cut the tart into wedges with a sharp knife and serve with vanilla ice cream.