2 dark-chocolate peanut butter cups, chopped, for garnish
Place cashews in a bowl and cover with cool water. Cover bowl and refrigerate for at least 4 hours or overnight. Line a muffin tin with 8 paper or foil liners.
Make crust: In a food processor, pulse peanuts, dates, cacao and salt to mix, then blend until a dough forms. Divide among muffin cups (use about 1 ½ tbsp per cup) and press on the bottoms to form crusts. Freeze. Wipe out processor.
Drain cashews; rinse under cool water. Place in processor. Add coconut cream, collagen, peanut butter, maple syrup, and salt; blend until smooth, stopping to scrape down processor a few times. (Yield: About 2 cups) Remove muffin tin from freezer and divide filling among cups, using about 3 to 4 tablespoons batter for each.
Sprinkle chopped peanut butter cups on top, cover and freeze until filling is firm, at least 3 hours. Let stand on counter for about 10 minutes to thaw before serving.