Preheat oven to 350 degrees. Place coconut on a baking sheet, and place in oven to toast for 8 to 10 minutes, stirring halfway through.
In a medium bowl, mix together 1 cup coconut, graham cracker crumbs, melted butter, and 1 tablespoon sugar.
Press mixture into a 10-inch pie plate and refrigerate. Note: You can also use a 9-inch plate. The filling will just be piled higher.
In a 3-quart saucepan, whisk together milk and gelatin. Let stand 1 minute. Cook over medium heat, stirring continuously, 1 minute or until gelatin dissolves.
Stir in pumpkin, salt, cinnamon, nutmeg, ginger, egg yolks, and 1/2 cup sugar.
Cook and stir mixture for 5 to 7 minutes. Do not let boil. Turn heat down if it starts to bubble.
Pour mixture into a bowl and refrigerate for 40 minutes, stirring halfway through.
About 15 minutes before the 40 minutes is up, beat egg whites at high speed with a whisk attachment until soft peaks form, about 8 to 10 minutes.
Slowly add 1/4 cup sugar to egg whites and beat until stiff peaks form, about 2 to 3 minutes.
Add 1/3 of egg white mixture into pumpkin mixture and fold in using a rubber spatula. Fold in another third and then the remaining egg whites.
Pour into crust and chill 2 hours.
Beat mascarpone cream and heavy whipping cream until soft peaks form. Gradually add sugar and vanilla and beat until mixture is stiff. Spread on top of pie. Sprinkle with remaining coconut and serve. Store leftovers in refrigerator.
Notes
Serve pie chilled. You can toast the coconut in a nonstick skillet instead of the oven. Instead of using the mascarpone in the whipped topping, you can double the heavy cream. Eggs are easier to separate when they are cold, but egg whites whip better at room temperature. Separate the eggs just after removing from the refrigerator and let the egg whites sit on the counter for about 15-20 minutes before beating. Not much longer though since the egg whites are not going to be cooked.