Let’s assemble this incredibly fun No-Bake Funfetti Oreo Birthday Cake Cheesecake! Remember the crucial heat-treating step for the cake mix first.

Heat-Treat the Cake Mix (Safety First!): Raw flour can contain harmful bacteria. Measure 1 cup of dry Funfetti cake mix. Oven Method: Spread it on a baking sheet and bake at 350°F (175°C) for 5 minutes. Microwave Method: Place in a microwave-safe bowl and microwave on high in 30-second bursts, stirring between each, until the mix reaches 160°F (71°C) on an instant-read thermometer. Let the heat-treated cake mix cool completely before using.

Make the Crust: While the cake mix cools (or beforehand), make the crust. Add the 25 Golden Birthday Cake Oreos and 2-3 tbsp sprinkles to a food processor. Pulse until they form fine crumbs. Transfer crumbs to a bowl. Add the 1/4 cup melted butter and stir until well combined and all crumbs are moistened.

Press the crumb mixture firmly into the bottom and about halfway up the sides of a 9-inch springform pan. Use the bottom of a flat glass to help pack it tightly. Place the pan in the refrigerator to firm up while you make the filling.

Make the Filling: In a large bowl, beat the 24 oz (3 packages) of room temperature cream cheese and 1/2 cup granulated sugar together with an electric mixer until completely smooth and creamy. Scrape down the sides of the bowl.

Add the 1 tsp vanilla extract, the 1 cup cooled heat-treated Funfetti cake mix, and 2 tbsp milk. Mix on low speed, then medium, until well combined and smooth.

Add the 8 oz container of thawed Cool Whip (or stabilized homemade whipped cream). Gently fold it into the cream cheese mixture using a large rubber spatula until just combined and no streaks remain. Avoid overmixing.

Now for the fun bits! Add the 1 1/2 cups Oreo crumbs, the chopped 7-10 Oreos, and the 6 tbsp sprinkles to the filling. Gently stir these in with the spatula just until they are evenly distributed throughout the creamy filling.

Assemble and Chill: Pour the loaded filling evenly into the chilled Oreo crust in the springform pan. Smooth the top with your offset spatula or the back of a spoon.

Cover the pan loosely with plastic wrap. Refrigerate until the cheesecake is firm, which usually takes at least 4-5 hours, but longer (even overnight) is often better for easier slicing.

Finish and Decorate: Once the cheesecake is firm, carefully run a thin knife around the edge if needed, then release and remove the sides of the springform pan. Transfer the cheesecake (still on the pan base or carefully slid onto a platter) back to the fridge while you make the topping.

To make the whipped cream topping, add the 3/4 cup cold heavy cream, 6 tbsp powdered sugar, and 1/2 tsp vanilla extract to a large, clean bowl (preferably chilled). Whip with an electric mixer on high speed until stiff peaks form.

Transfer the whipped cream to a piping bag fitted with a large star tip (like 1M) if desired. Pipe decorative swirls around the top edge of the chilled cheesecake. Alternatively, simply spread the whipped cream decoratively over the top.

Garnish the whipped cream swirls or topping with additional Golden Birthday Cake Oreo crumbs and halved Golden Birthday Cake Oreos, if desired.

Refrigerate the finished cheesecake until ready to serve. Slice with a large, sharp knife, wiping the blade clean between cuts. Enjoy the party!