Preheat the oven to 350°F (175°C).

In a mixing bowl, whisk together the flour, baking soda, salt, and cinnamon.

In another bowl, combine the prune juice, brown sugar, butter, egg, and vanilla extract. Mix until well combined.

Gradually add the dry ingredients to the wet ingredients, stirring until just combined.

Fold in chocolate chips and nuts if using.

Drop tablespoonfuls of dough onto a baking sheet lined with parchment paper.

Bake in the preheated oven for 10-12 minutes or until the edges are golden.

Allow cookies to cool on the baking sheet for a few minutes before transferring to a wire rack to cool completely.