The topping here calls for pine nuts, but you can substitute any soft, oily nut, like walnuts or pecans. Heat the oven to 350 F. Spread the pine nuts out on a baking sheet and bake until very lightly browned, about eight minutes. Stir the nuts on the sheet once or twice as they cook so they brown evenly. Cool them completely. While the pine nuts are cooling, make the berry filling: Stir 1/2 cup granulated sugar, the cornstarch, orange zest and ginger together in a large bowl until blended. Add the blueberries and toss gently. Let stand, tossing gently occasionally, until the blueberries start to get juicy. Scrape the berries into an 11-inch oval baking dish. Dot the top with the 3 tablespoons butter cut into small pieces.Make the topping: Stir the flour, brown sugar and 1/3 cup granulated sugar together in a small bowl until blended. Add the 6 tablespoons room temperature butter and cooled pine nuts and rub the ingredients together with your fingertips until the butter is completely absorbed by the flour and sugar. (It is fine if some of the pine nuts are broken up and some are whole.) Sprinkle the topping evenly over the berries and bake until the topping is lightly browned and the berries are bubbling and lightly thickened, about 40 minutes. Remove and cool at least 45 minutes before serving.