Place all 36 Oreo cookies (cream and all) in a food processor and pulse until you have fine, even crumbs with no large chunks. If you don’t have a food processor, add the cookies to a heavy zip-top bag, remove excess air, and crush very finely with a rolling pin.

Add the softened cream cheese to the Oreo crumbs. If using vanilla extract, add it now. Pulse again in the food processor or stir together with a sturdy spatula until the mixture is fully combined and forms a soft, thick dough that holds together easily when pressed.

If the mixture feels very soft or sticky, chill the bowl in the refrigerator for 15–20 minutes to firm it up. This will make rolling neater truffle balls easier.

Line a baking sheet with parchment paper. Using a small cookie scoop or a tablespoon, portion the mixture and roll each portion between your palms to form smooth balls about 1–1.25 inches in diameter. Place the rolled balls on the prepared baking sheet.

Refrigerate the tray of Oreo balls for 30–45 minutes, or place in the freezer for 15–20 minutes, until the truffles are firm and cold. This helps them keep their shape when dipping.

Place the chopped chocolate or candy melts in a microwave-safe bowl. Microwave in 20–30 second bursts, stirring well after each interval, until completely melted and smooth. If the chocolate is too thick for dipping, stir in 1–2 teaspoons of coconut oil or shortening to thin it slightly. Avoid overheating to prevent the chocolate from seizing.

Working with a few chilled Oreo balls at a time, drop one ball into the melted chocolate. Use a fork to gently roll and coat it completely. Lift it out with the fork, allowing excess chocolate to drip off, tapping the fork gently on the side of the bowl. Slide the coated truffle back onto the parchment-lined sheet, using a toothpick or another fork to help release it if needed.

While the chocolate coating is still wet, immediately top each truffle with sprinkles, crushed Oreos, or a pinch of flaky sea salt if desired. If using melted white chocolate or colored candy melts for drizzling, allow the base coat to firm up first, then drizzle decoratively over the tops.

Allow the dipped truffles to sit at room temperature until the chocolate is fully set, or chill them in the refrigerator for 10–15 minutes to speed things up. Once set, you can trim any excess chocolate around the bases for a cleaner look if desired.

Arrange the finished Oreo truffles on a serving plate, in mini cupcake liners, or in gift boxes or tins. Serve chilled or slightly cool, and store any leftovers in the refrigerator.