Line the bottom and sides of an 20cm x 20cm square baking tin with greaseproof / parchment paper.
In a large saucepan over a gentle heat, place the almond butter, honey and cinnamon. Then stirring constantly, allow these to melt and infuse together. Remove from the heat.
Stir in the oats and dark chocolate chips and combine the mixture well together.
Put the combined sticky mixture into the lined baking tin and flatten it out all over by pressing down with the tips of your fingers making sure the bottom of the tin is evenly lined.
Place the baking tin into the fridge overnight.
In the morning, remove from the fridge, lift out the hardened slab using the greaseproof paper onto a cutting board, and cut into 16 bars.
Store in a fridge in an airtight container to keep as fresh as possible until time to eat.