Bake 1 frozen pie shell according to package directions. Let cool.
Place 3–4 cups sliced strawberries into the bottom of the cooked pie shell. The strawberries should mound just a little over the top of the pie crust.
Place 1 cup sugar, ¾ cup water, and 3 tablespoons cornstarch in a small saucepan. Bring to a boil. Remove from the heat and whisk in 1 (3 oz) package strawberry Jello.
Pour the gelatin mixture into the pie crust, giving it time to seep into all the nooks and crannies. Just fill to the top edge of the pie, so it doesn’t run over.
Refrigerate for 4–6 hours, or until firm.
Top with 8 oz whipped topping (use as much of it as you like) or whipped cream.
Notes
You can use a refrigerated pie crust in place of the frozen pie shell. Bake it according to package directions. Want to use real whipped cream instead of whipped topping? Whip 1 cup of heavy cream with 1 tablespoon of powdered sugar and ¼ teaspoon vanilla extract until soft peaks form. You can keep the strawberries whole instead of slicing them, but note that the pie may not cut as nicely. Store any leftover pie in the refrigerator.