Pour the cold milk into a large bowl. Add the instant chocolate pudding powder and whisk vigorously for 2 minutes until smooth and slightly thickened. Let it sit for 5 minutes to set further. It will look loose at this stage. That is correct.

Fold the Cool Whip into the pudding gently until fully combined and fluffy. Do not beat it. The folding keeps the mixture light. The finished pudding should be pale brown, creamy and hold its shape when spooned. Refrigerate for 10 minutes while you prepare the cookies.

Place the chocolate sandwich cookies in a zip-lock bag, seal it, and crush with a rolling pin until you have fine, dark crumbs with some slightly larger pieces. You want it to look like dirt, which means not perfectly uniform. Some texture is correct. A food processor produces crumbs that are too fine and too uniform. The rolling pin is more authentic and considerably more satisfying.

Spoon a layer of crushed cookie crumbs into the bottom of each clear cup, about 2 tablespoons. Add a layer of the pudding mixture on top, filling the cup about halfway. Add another layer of cookie crumbs. Top with a final layer of pudding, leaving about an inch of space at the top. Finish with a generous layer of cookie crumbs on top so the surface looks convincingly like dirt.

Press 3 to 4 gummy worms into the top layer so they appear to be emerging from or disappearing into the dirt. Some should hang over the edge of the cup. At least one should be buried slightly so only the tail is visible. This is not decoration. This is the entire point.

Refrigerate for at least one hour before serving. The cookie crumbs will soften slightly against the pudding, which is correct and produces a better texture than crisp crumbs throughout.