Line an 8x8-inch pan with parchment paper or foil, leaving an overhang for easy removal. Line a large sheet pan with a silicone liner or parchment paper. Set both pans aside.

Place all 36 whole Oreos (cookie and filling) in a food processor or blender. Pulse until you have a fine, even crumb, reprocessing any large pieces. Transfer the crumbs to a large mixing bowl.

Add the 8 ounces softened cream cheese to the Oreo crumbs. Use a stand mixer or hand mixer to beat until fully combined and smooth, with no visible streaks of cream cheese.

Press the Oreo–cream cheese mixture evenly and firmly into the prepared 8x8 pan to form a compact layer. Cover and refrigerate for at least 2 hours (or freeze for 1 hour) until firm.

Lift the chilled mixture from the pan using the overhang and place it on a flat work surface. Use a heart-shaped cookie cutter to cut out hearts, pressing straight down and lifting each shape out. Reroll any scraps and cut additional hearts or roll scraps into small balls for dipping. Place all cut pieces on the lined sheet pan.

Put 2 cups (12 ounces) chocolate melting wafers and 2 teaspoons coconut oil in a microwave-safe glass bowl. Microwave in 15-second increments, stirring between each interval, until the chocolate is fully melted and smooth. Let the chocolate sit about 5 minutes to cool slightly before dipping.

One at a time, use a fork to lower a heart into the melted chocolate and fully coat it. Lift the fork, tap it on the edge of the bowl to remove excess chocolate, use a toothpick to pop any air bubbles, then use the edge of a table knife to slide the coated truffle off the fork onto the lined sheet pan.

If desired, immediately sprinkle with Oreo crumbs while the coating is wet, or wait until the chocolate firms slightly before drizzling with optional melted white chocolate.

Refrigerate the coated truffles for at least 1 hour to allow the chocolate to set. Store refrigerated.