Prepare the crust by combining graham cracker crumbs, melted unsalted butter, and granulated sugar until it reaches a consistency similar to wet sand. Press this mixture into the bottom of a 9-inch springform pan and chill in the refrigerator for at least 15-20 minutes.

In a mixing bowl, beat softened cream cheese and powdered sugar until the mixture is smooth and creamy, about 2-3 minutes. Add vanilla extract, orange zest, and fresh orange juice, mixing well to combine.

Whip heavy whipping cream until stiff peaks form, about 3-5 minutes. Gently fold the whipped cream into the cream cheese mixture, being careful not to deflate it. If using gelatin, dissolve it in warm water and fold it into the filling.

Pour the creamy filling over the chilled graham cracker crust. Smooth the top with a spatula. Cover with plastic wrap or aluminum foil and refrigerate for a minimum of 4 hours, or ideally overnight, to set.

Remove the cheesecake from the springform pan, top with whipped cream, and garnish with fresh orange slices and a sprinkle of orange zest. Slice and serve chilled.