Line a rimmed baking sheet with parchment paper.: The scent of a well prepared workspace sets the tone, and the parchment creates a nonstick landing for the truffles. You'll hear the rustle of the paper as you smooth it into place, and visually you want a clean surface so coated balls do not stick. This step avoids scrapped chocolate and frustrating removals later. A common misstep is skipping parchment, which can lead to stuck truffles and broken shells.
Place cookies in food processor and mix until cookies turn into fine crumbs. See notes if you don’t have a food processor.: When you pulse the Oreo cookies , the motor hums and the crumbs fall like fine dust, smelling richly of cocoa. Aim for a sand like texture so the filling is smooth, and tap the processor to redistribute any larger bits. If you do not have a food processor, the bag and rolling pin method works but requires elbow grease. Over processing with cream cheese later can make the mixture too loose, so keep this step strictly to drying the cookies.
Add cream cheese and peppermint extract to the cookie crumbs. Mix with a silicone spatula or with a hand mixer on low until a dough forms. Do not mix the mixture in the food processor as the cream cheese mixture can become too liquidy.: After combining flavors you will notice the aroma shift as the tangy cream cheese melts into the crumbs and the peppermint lifts the blend. Use a silicone spatula or low speed with a hand mixer to fold until the mixture holds together like play dough. The texture should be pliable not runny; if it becomes too loose that often means the cream cheese was too warm or overmixed. Avoid using the food processor now, as it can overwork and liquefy the mixture.
Roll the dough into balls, about one tablespoon per truffle. I like to use this cookie scoop set, for this recipe you'll need the small cookie scoop. Place each truffle on the parchment paper-lined baking sheet so they are not touching. Freeze the truffles for at least 15 minutes.: Rolling is tactile and satisfying, with the dough warming slightly under your palms and taking on a glossy sheen. I use a small cookie scoop for uniform size, then gently roll between my palms to seal any seams. Place them spaced on the parchment lined sheet so they do not touch. Freeze for at least 15 minutes to firm the centers, this helps when dipping. A problem to avoid is making balls that are too large, which will be harder to coat evenly and may cause the shell to crack under weight.
Add the peppermint white chocolate melting wafers and one tablespoon of coconut oil (optional) to a heatproof bowl. Place the bowl in the microwave and heat for a minute at half power, then stir. Continue heating the white chocolate in thirty-second increments until it forms a smooth white chocolate sauce.: The moment you begin melting the white chocolate you will notice the aroma change to sweet and creamy, and the texture moves from solid chips to a glossy pool. Heat gently in the microwave at half power, stirring frequently to distribute heat. The coconut oil helps the melted chocolate flow and gives a satin finish. If you heat too aggressively, the chocolate can seize and grain, so patience and stirring prevent that error.
Remove truffles from the freezer. Place truffle balls into white chocolate one at a time to coat, using a fork so excess chocolate can drip off. Place each white chocolate-coated ball on parchment paper so they are not touching each other and immediately sprinkle with crushed peppermint before the chocolate begins to harden.: As you stir the slowly melting wafers, the mixture becomes silkier and thicker, the sound is the soft swish of spoon against glass. Continue in thirty second increments until perfectly smooth, testing the pour with a spoon to ensure it coats. The reason for low heat is to preserve the glossy texture; overheating destroys the emulsion. A common mistake is rushing this stage, which leads to lumpy or separated chocolate.
Place the pan in the freezer for 15 minutes to help the chocolate to fully harden, then enjoy!: The cold centers will feel firm when you touch them lightly, and that temperature difference is what makes the shell set quickly when dipped. Work straight away so the centers stay chilled, otherwise the heat of the chocolate can melt the interior. If the centers warm up they will be more likely to collapse under the coating, so keep them in the freezer until you are ready to dip.
Place truffle balls into white chocolate one at a time to coat: Using a fork, lower each chilled truffle into the melted white chocolate , letting excess drip back into the bowl. The dipping sound is quiet, but visually you should see a smooth, even layer form around the ball. Remove with care and place on parchment. Immediately sprinkle with crushed peppermint candies while the chocolate is still wet so they adhere. Rushing or dipping with warm centers will cause the shell to crack or the filling to ooze.
Place each white chocolate coated ball on parchment paper so they are not touching each other and immediately sprinkle with crushed peppermint before the chocolate begins to harden: The little sparkle of crushed peppermint against glossy white chocolate is very satisfying visually, and the aroma becomes fresher. Doing this while the coating is tacky ensures the pieces stick firmly. If you wait until the chocolate fully hardens, the peppermint will slide off and look careless, so timing is important.
Place the pan in the freezer for 15 minutes to help the chocolate to fully harden: The freezer helps the shell set quickly and gives a clean snap when you bite into the truffles. After chilling, the surface will appear matte and firm to the touch, and handling them will not leave fingerprints. Do not overfreeze for hours as extreme cold can cause condensation when they come back to room temperature, which may affect texture. A common error is leaving them in the freezer uncovered, which can invite odors to cling to the treats.
Then enjoy: When you bite in you'll notice the contrast of cool, creamy center and crisp coating, with a refreshing hint of peppermint . Serve them slightly chilled for best texture, and expect them to disappear fast. If you find any truffles that did not set properly, place them back in the freezer briefly to firm up before serving.