Grease a 9- or 10-inch springform pan liberally with cooking spray. Set aside.

Pour the 6 cups Rice Krispies cereal into a large mixing bowl; set aside for now.

In a medium saucepan over low heat, melt the ¼ cup salted butter together with the 10 oz package of miniature marshmallows, stirring constantly until the mixture is fully melted and smooth.

Immediately pour the melted marshmallow-butter mixture over the cereal in the bowl. Toss gently and thoroughly until the cereal is completely coated with the marshmallow mixture.

Transfer the coated cereal mixture into the prepared springform pan. Using a greased glass cup (or the bottom of a greased drink glass), press the cereal mixture firmly into the bottom and up the sides of the pan to form the crust and sides.

Let the crust set in the pan for about 20 minutes while you prepare the filling.

In the bowl of a stand mixer (or using a hand mixer) combine the softened cream cheese, ½ cup sugar and 1 tsp vanilla extract. Beat until smooth and creamy, about 1 minute.

Add the 7 oz jar of marshmallow creme/fluff to the cream cheese mixture and beat until smooth and fully incorporated.

Gently fold in the thawed 8 oz pkg of Cool Whip by hand (do not over-mix) until the filling mixture is fluffy and well combined.

Spread the filling mixture evenly into the prepared rice krispy crust, smoothing out the top with a spatula.

Pipe or dollop whipped cream around the perimeter of the cheesecake. Then, arrange the cubed prepared Rice Krispy Treat squares in the centre of the cheesecake for garnish.

Cover and refrigerate the cheesecake for at least 2 hours (or until set) before removing from the springform pan and slicing to serve.