Add 36 golden Oreo cookies to a food processor and pulse until they become fine crumbs.
Add 6 tablespoons melted salted butter and blend until fully combined, and the mixture resembles damp sand.
Press the cookie mixture firmly and evenly into the bottom of a 9 x 13-inch baking dish, then refrigerate while preparing the subsequent layers.
Cream Cheese Layer
Add 16 ounces softened cream cheese, ⅔ cup granulated sugar, and 1 tablespoon orange zest to a large bowl, then beat with a hand mixer or stand mixer until smooth.
Carefully spread the cream cheese mixture evenly over the chilled crust, then return it to the refrigerator.
Orange Layer
Heat ½ cup freshly squeezed orange juice in the microwave or stove top until simmering, then add it to a small bowl with 1 (6-ounce) box orange gelatin and 2 tablespoons fresh orange zest. Whisk until the gelatin is completely dissolved. Set aside to cool.
Add 1 (3.4-ounce) box instant vanilla pudding mix and 1 ½ cups milk to a large bowl and use a hand mixer or whisk by hand until thickened.
Whisk the cooled orange gelatin into the vanilla pudding until smooth and fully combined.
Pour the orange mixture over the top of the cream cheese layer and smooth evenly, then return to the refrigerator to set for 10-15 minutes.
Whipped Topping Layer
Once the orange layer is slightly set, spread 1 (8-ounce) container thawed whipped topping evenly over the top. Cover with plastic wrap and chill for at least 4 hours.
Before serving, garnish the top with 1 (11-ounce) can mandarin oranges and fresh mint leaves.
Notes
Leftover and Make Ahead Instructions
Fridge: Cover tightly with plastic wrap or an airtight lid and store in the fridge for up to 5 days.
Freezer: This can be frozen in a freezer-safe dish for up to 3 months. Cover tightly with 2-3 layers of plastic wrap, then carefully wrap the whole dish in 2 layers of heavy-duty aluminum foil. Can be served directly from frozen, or left in the refrigerator overnight to thaw before serving.
Make Ahead: This is a great make-ahead dessert! Make it 1-2 days in advance, but wait to garnish with the mandarin oranges until you serve it.