How about this version for a change of pace from strawberry rhubarb? The tartness of the rhubarb brings out the blueberry flavour of the berries. Serve with a scoop of vanilla ice cream.
 
Makes 1 pie
 
1 double crust pastry recipe
4 cups (1L) chopped fresh or frozen rhubarb
2 cups (500 mL) fresh or frozen blueberries
2/3 cup (160 mL) granulated sugar
1/3 cup (80 mL) flour
1 egg
3 tsp (15 mL) butter
1 egg, beaten
granulated sugar, for sprinkling
 
Preheat oven to 425°F (220°C).
 
Divide the pastry in half and form each half into a ball. On a floured surface, roll out one of the balls to line the bottom of a standard pie plate. Roll out the top crust. Refrigerate the pastry while you make the filling.
 
In a large bowl, combine the rhubarb, blueberries, granulated sugar, flour and the egg. Mix well.
 
Transfer to the prepared pie plate. Top the filling with three dots of butter. Cover with the top crust. Trim and seal the edges. Make slits in the top crust to allow steam to escape. Brush the top with the beaten egg and sprinkle with sugar.
 
Bake for 15 minutes. Lower the heat to 350°F (180°C) and bake another 35 minutes, or until the filling is bubbly and the crust is golden brown.