Prepare and prebake the pie crust according to packaging or your favorite recipe instructions for a single crust pie.
Meanwhile, in a large saucepan combine the sugar and cornstarch. Stir in the butter, berries, lemon juice, and cinnamon and stir occasionally over medium heat until the mixture comes to a boil.
Remove the filling from heat and pour into the prepared pie crust. cool completely on a wire rack. Usually, 6 to 8 hours to ensure the pie has fully set.
Notes[]
Serve with ice cream or whipped cream, garnish with mint leaves, if desired.