Preheat oven to 350°F.
Unroll the pie crust into a 9" pie pan; crimp the edges however you'd like.
1 uncooked refrigerated pie crust*
In a large bowl, combine all filling ingredients with a whisk; set aside.
1 15-ounce can pumpkin puree, 1 12-ounce can evaporated milk, 2 eggs, 1/2 teaspoons salt, 1 tablespoon pumpkin pie spice, 3/4 cup sugar
In another bowl, combine the topping ingredients with a fork until crumbly and set aside.
1/4 cup salted butter, 1/4 cup brown sugar, 1/2 cup quick cooking oats, 1/2 cup Gingersnap cookie "flour"
Pour the filling into the pie shell and carefully sprinkle the topping over the filling.
Cover the edge of the pie crust with aluminum foil to protect it from turning too brown before the rest of the pie is done.
Bake for 45 minutes; remove the foil.
Bake an additional 10 minutes.
Let cool on the counter then refrigerate. Serve with whipped topping, if desired, and enjoy!