In a food processor, combine all the ingredients and chop them until a paste is formed. Don’t chop them so much that you can’t see little bits of walnuts, apples, and dates.
Test to see if the mixture binds together. If not, add a bit of water (up to a tablespoon).
Transfer the mixture to an 8 x 8 pan lined with wax paper. Press down evenly.
Refrigerate for at least two hours, and then cut it into 8 bars.
Store the bars in an airtight container in the refrigerator.