Moonlit Blueberry Pie with Almond Creme Chantilly

4 cups fresh blueberries, washed
3/4 cup granulated sugar
1/2 cup water
2 tablespoons cornstarch, dissolved in 2 tablespoons water
1 (9-inch) deep dish pie shell, baked
1 tablespoon butter
4 tablespoons Cointreau liqueur
1/4 cup slivered almonds, toasted

Combine 1 cup of the blueberries, sugar and water in blender and pur