Preheat oven to 325°F. In a large bowl, combine graham cracker crumbs and sugar. Add the melted butter and stir until combined. Dump the mixture into a 9½ inch pie plate. Press it into the bottom and a little more than halfway up the sides of the pie dish. I use the bottom of a drinking glass or measuring cup to help pack it in. Bake for 8-10 minutes, until golden and fragrant. Set aside to cool to room temperature, then transfer to the freezer for one hour. Meanwhile, prepare the blueberry sauce.

in a small saucepan over medium heat, whisk orange juice, sugar, and cornstarch. Bring to a simmer, then add 1 pint blueberries minus ¼ cup that's been set aside for the topping. Simmer, stirring frequently, until the mixture is thickened and some of the blueberries have burst, about 4 minutes. Stir in lemon juice. Transfer to a bowl and cool slightly, then refrigerate to cool completely.

Remove crust from freezer and fill the crust with scoops of ice cream. Drizzle about half of the blueberry sauce around the ice cream and press the ice cream into a flat layer (you can also swirl some of the blueberry sauce into the top using a butter knife). Refrigerate the remaining blueberry sauce for topping the pie when it is served.

Cover the pie and place in the freezer until frozen solid, preferably overnight.

Allow the pie to sit at room temperature for at least 10 minutes to soften slightly. Meanwhile, whip heavy cream, sugar, and vanilla until soft peaks form. Pipe or dollop the whipped cream onto the pie and decorate with fresh berries (including the reserved ¼ cup blueberries). Serve each slice with a little extra blueberry sauce.