Preheat the oven to 350°F (175°C).
If using fresh huckleberries, rinse and drain them. If using frozen, thaw and drain excess liquid.
In a medium saucepan, combine huckleberries, ½ cup sugar, cornstarch, and lemon juice. Cook over medium heat, stirring gently until the mixture starts to thicken and bubble, about 5-7 minutes. Remove from heat and let it cool.
In a mixing bowl, add heavy whipping cream, the remaining sugar, vanilla extract, and salt. Whip until soft peaks form.
Once the huckleberry mixture is cool, gently fold half of the whipped cream into the huckleberry mixture until combined, taking care not to deflate the whipped cream.
Spoon the combined huckleberry and whipped cream mixture into the pre-made pie crust. Smooth the top with a rubber spatula.
Spread the remaining whipped cream over the top of the pie for decoration.
Cover the pie with plastic wrap or aluminum foil and refrigerate for at least 2 hours before serving to allow the flavors to meld and the dessert to set.
Slice, serve, and enjoy!