Add the 15 Oreos to a food processor or a storage bag. Pulse until crumbs form if using a food processor or crush with a rolling pin.
Add the 3.4 ounce box instant chocolate pudding and 2 cups cold milk to a large bowl. Whisk until the pudding comes together and thickens. Let rest for 5 to 10 minutes until it’s set up.
While the pudding is setting up, add the 1 cup heavy whipping cream and 1 1/2 tablespoons powdered sugar to a large mixing bowl. Using a hand mixer, beat on medium speed until stiff peaks form.
Add the whipped cream into the thickened pudding mixture. Whisk until completely combined.
Add the pudding whipped cream mixture to a piping bag fitted with a large round piping tip.
Fill a 9 ounce clear cup with the whipped cream, leaving about 1/2 to 1 inch space at the top for the crushed Oreos.
Add 3 gummy worms to the top of the pudding whipped cream.
Divide the crushed Oreos to the top of the cups. Make sure to push some crumbs under the worms as well as on top.
Store in an airtight container in the fridge until you're ready to serve.
Notes
You can add layers of oreo and pudding whipped cream instead of just adding the crumbs at the top.Storage: Store in an airtight container in the refrigerator for up to 4 to 5 days.