3 cups all-purpose flour
¼ cup packed light brown sugar
3 tablespoons granulated sugar, plus additional for sprinkling
1 teaspoon ground ginger
3½ teaspoons baking powder
¾ teaspoon kosher salt, finely ground
12 tablespoons (1 1/2 sticks) butter
1½ cups heavy cream, plus additional for brushing
1 pound strawberries, sliced
1 pound rhubarb, chopped
1 cup granulated sugar
½ vanilla bean
1 tablespoon cornstarch
1 tablespoon vanilla extract
Vanilla or buttermilk ice cream
Make the biscuit topping: Mix together the flour, brown sugar, 3 tablespoons granulated sugar, ginger, baking powder, and salt in a large bowl. Cut the butter into small pieces and rub into the flour mixture until it resembles coarse meal. Add about 1 1/2 cups heavy cream and mix until it forms a dough (you might not need all the cream). Wrap the dough in plastic wrap and chill for at least 1 hour.
Make the fruit mixture: Combine the strawberries, rhubarb, granulated sugar, and vanilla bean in a large bowl. Let stand for 1 hour. Remove the vanilla bean and pour off half of the liquid, then stir in the cornstarch and vanilla extract. Pour the fruit into a 13 x 9-inch baking dish.
Preheat the oven to 350°F.
Roll the dough out on a floured surface to ¼ inch thick and cut into circles or any desired shape. Place the dough on the fruit mixture without overlapping any pieces. Brush the top of the dough with heavy cream and sprinkle with granulated sugar. Bake the cobbler for about 25 minutes or until the dough is golden brown and the fruit is bubbling in the center.
Serve warm with ice cream.