Place Thin Mints or Keebler Grasshopper Cookies in a food processor with the cream cheese and process until the mixture starts to form a ball. Alternately, you can crush the cookies in a bag without a food processor and then work in the cream cheese with a hand mixer and your hands until it comes together.
Crumble the mixture over the cooled brownies. Press to entirely cover. It will seem like there’s not enough, but there is. Just keep pressing (but gently, so you don’t rip the brownies).
Melt the chocolate chips and Crisco in a medium bowl on HIGH in 30 second increments, stirring between each. (It will take about 1 1/2 minutes to become smooth.) Pour over truffle mixture and spread evenly. Chill until set.
Let the brownies sit at room temperature at least 20 minutes before slicing into squares. Store in an airtight container. They can be frozen for up to one month.