In a mixing bowl, combine graham cracker crumbs and granulated sugar. Stir in the melted unsalted butter until it resembles wet sand. Press this mixture firmly into the bottom of a 9-inch springform pan. Chill in the refrigerator for about 30 minutes.

In a large mixing bowl, beat the softened cream cheese until smooth and creamy, about 2–3 minutes. Gradually add marshmallow fluff and vanilla extract, mixing until fully combined.

Gently fold in the whipped topping into the cream cheese mixture using a spatula, maintaining the airy texture.

Pour the creamy filling over the chilled graham cracker crust in the springform pan, and smooth it out. Cover with plastic wrap and refrigerate for at least 4 hours.

When ready to serve, remove the springform ring and add toppings as desired. Slice and serve chilled.