In a mixing bowl, combine the crushed Oreo cookies and softened cream cheese. Mix well using an electric mixer or spoon until fully incorporated and smooth.
Use your hands to form small balls (about 1 inch in diameter) from the mixture, and place them on a baking sheet lined with parchment paper.
Once all the Oreo balls are formed, place the baking sheet in the freezer for about 15 minutes, or until the balls are firm.
While the Oreo balls are chilling, melt the chocolate chips in a microwave-safe bowl in the microwave, heating in 30-second intervals and stirring in between until fully melted. Stir in vegetable oil for a smoother texture if desired.
Remove the Oreo balls from the freezer. Using a fork, dip each ball into the melted chocolate, ensuring it is fully coated. Let the excess chocolate drip off before placing them back on the parchment-lined baking sheet.
Once all the balls are coated in chocolate, sprinkle some crushed Oreos or festive sprinkles on top if desired.
Place the baking sheet into the refrigerator for about 20-30 minutes, or until the chocolate has completely set.