Step 1: Prepare the Oreo Crumbs: In a food processor, finely crush the entire package of Oreo cookies. Alternatively, place them in a large Ziploc bag and crush with a rolling pin until fine crumbs are formed. Set aside.
Step 2: Make the Cream Cheese Base: In a large mixing bowl, beat the softened butter and cream cheese together with an electric mixer until smooth and creamy. Add the powdered sugar and continue to beat until well combined and fluffy, scraping down the sides of the bowl as needed.
Step 3: Prepare the Pudding: In a separate large bowl, whisk together the instant chocolate pudding mixes and cold milk for about 2 minutes, or until the pudding starts to thicken. Let it sit for 5 minutes to set up fully.
Step 4: Combine the Creamy Layers: Gently fold the thawed whipped topping into the cream cheese mixture until no streaks remain. Then, gradually fold the thickened chocolate pudding into the cream cheese and whipped topping mixture until everything is well combined and smooth. Be careful not to overmix.
Step 5: Assemble the Dirt Cake: Choose a large serving dish, such as a 9x13 inch pan or a trifle bowl. Spread approximately one-third of the crushed Oreo crumbs evenly over the bottom of the dish.
Step 6: Add the Creamy Filling: Carefully spoon half of the chocolate cream cheese mixture over the Oreo layer, spreading it gently to cover the crumbs.
Step 7: Layer Again: Sprinkle another third of the crushed Oreo crumbs over the creamy filling. Add the remaining half of the chocolate cream cheese mixture and spread it out smoothly.
Step 8: Final Layer: Top the cake with the remaining crushed Oreo crumbs, ensuring the entire surface is covered to resemble 'dirt'.
Step 9: Chill and Garnish: Cover the dish tightly with plastic wrap and refrigerate for at least 4 hours, or preferably overnight, to allow the flavors to meld and the cake to set. Before serving, arrange gummy worms on top, peeking out from the 'dirt' for a classic look.