To the bowl of a food processor add the walnut pieces together with the brown sugar, lemon zest, and a pinch of salt. Use the pulse button and process until the mixture resembles wet sand.

In a medium mixing bowl combine the apricot jelly with the water and vanilla extract. Add the walnut mixture. Use a spatula and combine everything until a dough is formed. Sprinkle in the walnut or almond flour and combine again until incorporated. Cover the bowl and refrigerate the cookie dough for 20 minutes.

Preheat your oven to 375°F. Prepare a small bowl with powder sugar and have a cookie sheet lined with parchment paper ready.

Use a tablespoon and scoop out the cookie dough, shape into a round ball. Alternatively, use your finger to help push the dough out of the spoon straight into the powder sugar bowl. Toss to coat lightly then transfer to the cookie sheet. Repeat with the remaining cookie dough and make sure to leave plenty of space between the cookies.

Bake the cookies for 13 minutes, turn off the heat and allow cookies to sit in the oven for 2 extra minutes. Transfer to a cooling rack and allow to cool off completely.