PIE CRUST

1 cup all-purpose flour
1/8 teaspoon salt
5 tablespoons cold unsalted butter, cut into small pieces
2 to 3 tablespoons ice water

TOPPING

3/4 cup sugar
1/2 cup all-purpose flour
1 teaspoon cinnamon
6 tablespoons cold unsalted butter, cut into small pieces
1/2 cup chopped pecans (2 ounces)

FILLING

1/2 cup fine pound-cake crumbs
2 pints blueberries
1 cup sugar
3 tablespoons cornstarch
3 tablespoons fresh lemon juice
1 teaspoon finely grated lemon zest
1 teaspoon cinnamon
Pinch of freshly grated nutmeg
Scant 1/2 teaspoon finely grated fresh ginger