In a food processor or blender blend the weetbix, flax seed meal and cacao until fine.
Add in the dates and blend until chopped finely.
Add in the tahini, coconut oil and maple syrup and blend it until it forms a sticky dough.
Press the mixture in a loaf tin lined with baking paper or plastic wrap and press down with your fingers to flatten it.
Place the tin in the freezer for 5 minutes while you melt the 50gr of chocolate. Then spread the melted chocolate on top of the slice and leave it to set in the freezer 20 minutes before slicing.
Store in the fridge in airtight container for up to 1 week or in the freezer to stock for lunchboxes.