1/2 cup butter, softened (125 mL)
1/2 cup sugar (125 mL)
1 egg
1/2 teaspoon almond extract (2 mL)
1 1/2 cups flour (375 mL)
1 1/2 teaspoons baking powder (1 mL)
1/4 teaspoon salt (1 mL)
FILLING:
5 cups fresh or frozen blueberries (1.25 L)
2 tablespoons orange liqueur (25 mL)
1 teaspoon finely grated lemon rind (5 mL)
2 cups sour cream (500 mL)
2 egg yolks
1/2 cup sugar (125 mL)
1/2 teaspoon almond extract (2 mL)

Preheat oven to 350ºF (180ºC).

In large bowl, beat butter with sugar until blended. Beat in egg and almond extract.

In separate bowl, whisk together flour, baking powder and salt; pour over batter and stir until blended. Pat over bottom and 2 inches (5 cm) up side of greased 10-inch (3 L) springfrom pan. Set aside.

FILLING:
Toss together blueberries, liqueur and lemon rind; scrape over crust. In bowl, whisk together sour cream, egg yolks, sugar and almond extract; scrape evenly over blueberries.

Bake in centre of oven for 1 1/4 hours or until crust is golden and crisp. Let cool in pan on rack. Refrigerate for 4 hours or until chilled. Remove side of pan. Cut into wedges to serve.