Pour the instant chocolate pudding mix into a mixing bowl. Add cold milk and whisk until the pudding is thick and smooth, about 2 minutes. This creates a rich, creamy base for your dirt dessert.
Transfer the prepared pudding to the refrigerator and let it chill for about 10 minutes to thicken further.
While the pudding chills, take your cookie crumbs and graham cracker crumbs. If using whole cookies, place them in a plastic bag and crush with a rolling pin until you have fine crumbs that resemble soil.
Once the pudding is set and thick, gently fold in half of the cookie and graham cracker crumbs to add texture and earthy color to the mixture.
Spoon the pudding mixture into a serving dish or individual cups, smoothing the top with a spatula or the back of a spoon.
Sprinkle the remaining cookie and graham cracker crumbs over the top to resemble dirt and create a layered, textured appearance.
Decorate the surface with gummy worms, inserting some partially into the crumbs to give the look of squirmy creatures hiding beneath the soil.
Let the assembled dirt cake sit in the refrigerator for at least 30 minutes before serving to allow the flavors to meld and the texture to firm up.
Once chilled, serve the dirt cake with gummy worms peeking out and enjoy the playful, crunchy, and creamy layers.
