Line a cookie sheet with parchment paper and set aside.
Place sugar cookies in a food processor and process until cookies turn into fine crumbs. Add cream cheese and process again until well-combined and mixture can be pressed into a ball, 1 to 2 minutes.2
Shape cookies into balls about 1-inch to 1 1/2-inches in diameter. Place on prepared cookie sheet and place in the freezer for 15 to 20 minutes.
While the truffles freeze, melt white chocolate in a medium bowl according to instructions. See notes below for tips on melting chocolate.3
Remove the cookie truffles from refrigerator. Using two forks, dip and roll chilled truffles, one at a time, in chocolate coating. Return to lined cookie sheet and immediately top with sprinkles. Repeat process for remaining truffles. Store in an airtight container in the fridge for up to a week or in the freezer for up to one month.4
Crumbly dough: If the sugar cookie truffle dough is not firm enough to roll into balls, add a teaspoon or two of milk.
Melting chocolate: Use melting wafers or candy melts. Microwave at 50% power level in 30 second intervals until chocolate is melted and smooth. Never add water to melted chocolate. If you need to thin out the chocolate, add a tablespoon of shortening or coconut oil. See more tips for how to melt chocolate here.
Freezing cookie truffles: Truffles can be frozen up to a month in advance. I suggest dipping them in chocolate before freezing for storage. Layer them between sheet of parchment paper in an airtight container. Defrost them in the refrigerator before serving.