Line a standard muffin tin with 8 parchment cups, and set aside.
To prepare the crust, pulse the walnuts and shredded coconut in a small food processor until ground into a fine meal. (Be careful not to over-process, or you'll wind up with nut butter instead!) Add the maple syrup, coconut oil and salt and process again until just mixed, and the dough sticks together when pinched between your fingers. Scoop the dough by heaping tablespoons into the 8 parchment cups and use your fingers to press down and form a crust for each cup. Place the pan in the fridge to set while you prepare the filling.
To prepare the filling, simply combine all of the ingredients in a blender, and blend until completely smooth and creamy. (If your dates aren't soft enough to blend easily, soak them in warm water for 10 minutes beforehand.) Remove the pan of crusts from the fridge, and pour the batter evenly into the 8 cups. Smooth the top, then return to the fridge to set completely, about 4-6 hours.
When the center of the filling is firm to the touch, the tarts are ready to serve!