Step 1

Add the walnuts to a food processor and process to break down into a coarse, grainy four with some small pieces.

Step 2

Add the rest of the ingredients except for the chocolate and process again until it forms a thick, sticky dough.

Step 3

Add the chocolate and pulse a few times to mix it into the dough.

Step 4

Line a standard-sized loaf pan with two overlapping strips of parchment paper that are long enough to stick out either side of the pan. Firmly press the dough into the pan, taking a few minutes to work it into every corner and smooth it out.

Step 5

Place in the fridge for a few hours or the freezer for about an hour.

Step 6

Lift and cut into 10 bars. Store the bars in the fridge for up to 2 weeks or freezer for up to 2 months.