Stir in grounded cookies and set in the fridge for half an hour. The pumpkin filling stayed slightly sticky even after being refrigerated for the half hour. Freeze them at least half an hour earlier than coating with chocolate. Hi Tammy, we suggest chilling the oreo truffle balls within the refrigerator for less than an hour. The coolness of the refrigerator will stratify the cocoa fats and the chocolate will look perfectly tremendous. 3. Begin stirring in a tight circle in the center of the bowl until you see a glossy chocolate emulsion start to form. Remember, the water should not be boiling or simmering, don't let the bottom of the bowl contact the water.