Start by combing your milled chia seeds with 3 tbsp of water. Stir thoroughly and to set to one side whilst you prepare the rest of your ingredients. (I mill my chia seeds using the milling blade that came with my Nutribullet but you can buy them separately.)
Pre-heat your oven to 180°C/350°F/Gas Mark 4.
Combine all of your ingredients into a food processor except for your cacao paste wafers. Add in your chia egg. Pulse a few times before processing until the dough comes together into a smooth ball. remove your dough and knead in your cacao paste wafers.
Lightly grease a 10" (25cm) cast iron skillet with a little coconut oil and press your dough in with the palm of your hand until evenly distributed.
Place your cookie into the oven and cook for roughly 20-25 minutes until lightly golden brown and firm to the touch. A toothpick should come out clean. Set to one side and leave to cool for 5 minutes before slicing and serving.
Recipe by Greens of the Stone Age at https://greensofthestoneage.com/paleo-and-vegan-skillet-cookie/