Line an 8x8 baking dish with parchment paper, making sure it goes up the sides. Use two sheets if needed for full coverage.

In a medium bowl, mix graham cracker crumbs and melted butter until fully combined. Press into the bottom of the baking dish in an even layer to form the crust.

In a large mixing bowl or the bowl of a stand mixer, beat the softened cream cheese and granulated sugar together until smooth and fluffy.

In a separate bowl, beat the heavy cream on high speed until stiff peaks form.

Add the whipped cream and rainbow sprinkles to the cream cheese mixture. Beat on low until just combined.

Pour the mixture over the prepared crust and spread into an even layer.

Cover the dish and refrigerate for at least 6 hours, or overnight, until fully set.

Slice into squares and serve chilled.