Prepare a standard sized loaf pan by lining with wax or parchment paper or even plastic wrap. Set aside.
For the shortbread, place the walnuts, coconut, honey, vanilla and salt in a food processor. Process just until no large pieces remain and the nuts and coconut are evenly ground and mixed. Pour into the prepared loaf pan and spread out evenly and press down firmly.
Prepare the raspberry filling by lightly mashing the berries with a fork. If using frozen berries, thaw before using and drain out any extra liquid sitting on top of the berries before lightly mashing. Stir in the honey and chia seeds and pour over the shortbread base.
Cover the bars with plastic wrap and refrigerate overnight. To remove, lift out the bars with the paper or plastic used to line the pan. Cut into equal sized bars and refrigerate up to a week or freeze 4-6 months and thaw before serving.