In a medium bowl, cover nuts with water and soak for 6 to 8 hours. Make crust: Line bottom of an 8 1/2-inch springform pan with parchment. Combine crust ingredients in a food processor; process until fine crumbs form. Press dough into prepared pan, pressing up along sides.
Make filling: Drain nuts completely. Combine nuts and filling ingredients in a food processor; process until completely smooth. Transfer filling to prepared piecrust and freeze until firm, at least 3 hours.
Adapted from Chocolate-Covered Katie, by Katie Higgins. Copyright 2015 by Katie Higgins. Used with permission from Grand Central Life & Style.