1. Put all the ingredients for the base into a bowl and mix them together with a fork until they come together into a dough. Roll the dough out into a rectangle about 14cm x 18cm (don't get hung up on exact measurements) and ½cm thick, then cut it into 10-15 smaller rectangles, each about 7cm long and 2½cm wide.
2. Take a baking tray that will fit into your freezer and line it with baking parchment. Put the 'bars' on the baking tray and place in the freezer. Leave to harden for 15 minutes.
3. In a food processor, blend together all the caramel filling ingredients except the nuts, adding as much water as you need to reach a nice thick paste.
4. Remove the bar bases from the freezer and spread a thick layer of the date caramel over each one, smoothing the sides with a knife. Sprinkle some chopped nuts on each of the bars, spreading them out evenly. Return the tray to the freezer and leave for another 20-30 minutes.
5. For the coating, melt the chocolate in a bowl over a pan of simmering water, making sure the base of the bowl doesn't touch the water.
6. Now it is chocolate covering time! Remove the bars from the freezer. We find the best way to coat the little bars is to put each one on a large knife, hold it over the bowl of the melted chocolate, the ladle the chocolate over, covering each with a lovely velvety layer! One at a time, cover them in the chocolate and put them back on the cold tray. The chocolate will harden almost instantly. Place in the fridge for an hour to firm up fully.
Stored in the fridge, these will keep for about a week.