Place some of the nonpareils in a small bowl. Set out 12 Oreo cookies. Open candy icing decorations. Line a baking sheet with parchment paper or wax paper.
Melt white chocolate chips and shortening according to your preferred method. I suggest on the stovetop in a double boiler. Stir until all the white chocolate is melted and the consistency is smooth.
1 11 ounce bag Ghirardelli White Chocolate Chips, 1 teaspoon Shortening, such as Crisco
Working with one cookie at a time, place one Oreo cookie in the melted white chocolate. Using a fork, flip the cookie over to coat it in the white chocolate. Make sure the cookie is covered. Lift the cookie out of the white chocolate and gently tap the fork on the side of the pan to allow the excess to drip off. Using a skewer or chopstick gently slide the cookie off the fork onto the prepared baking sheet.
Place one of the icing decorations in the center of the cookie. Sprinkle a few white nonpareils over the cookie to look like snow. Repeat with the remaining cookies working with one or two at a time.
Candy Icing Decorations, White Nonpariels
Allow white chocolate to set. Once all the cookie globes are set, you can begin putting the cookies on the bases (mini Reese's). If the white chocolate has begun to harden, melt it again. Dip the small side of the mini Reese's cup into the white chocolate and set it chocolate side up on the parchment-lined baking sheet. Gently place a cookie on top of the Reese's, and hold briefly so it will stay. The cookie will be verticle, standing on its side on the Reese's. See photos for reference. Allow to set before serving or storing.