In a mixing bowl, combine almond flour, coconut sugar, ground flax, and salt, stirring until evenly blended. Add melted coconut oil, water, and vanilla extract, mixing until a smooth dough forms.

Transfer the dough onto a piece of parchment paper and roll out to about ⅛" thickness. Cut into rectangles approximately 3.5" x 0.75".

Preheat the oven to 350°F (175°C). Place the cut rectangles on a baking sheet and bake for 8-10 minutes until lightly golden brown.

Allow the cookies to cool on the baking sheet for 5-10 minutes, then transfer to a wire rack to cool completely.

Prepare the filling by mixing together peanut butter and melted dark chocolate until smooth. Layer spoonfuls between two cookies, pressing together.

Melt more dark chocolate and dip each assembled cookie into it, ensuring full coating. Place back on parchment paper.

Let the coated bars sit at room temperature, then refrigerate until chocolate is firm, about 30-60 minutes.

Enjoy the Healthy Kit Kat Bars or store leftovers in a sealed container in the fridge for up to two weeks or freeze for two months.