Blend the dates and water well in a blender or food processor. Set aside.
In a mixing bowl, add the oats, cereal, cocoa powder, instant coffee and salt and whisk to combine. Set aside.
In a separate large mixing bowl, stir together peanut butter, honey and vanilla. (If the nut butter is too stiff, microwave for about 20 seconds to soften it up before adding the honey and vanilla.)
Add half the oat-cereal mixture into the nut butter bowl and blend until well-combined. Mix in the date paste and remaining oat-cereal mixture and continue to stir. You will need to push and mash the nut butter chunks to incorporate all the cereal.
Add the batter crumbles into the lined baking pan and press down using your fingers and palms to compress it and pack it in tightly, while evenly distributing it on the bottom of the pan and ensure it is neatly packed. If adding mini chocolate chips, scatter them over the top and press down with your fingers so they stick into the batter.
Place in the fridge to firm up for at least 30 minutes.
Lift the parchment paper out of the pan and place on a flat cutting board.
Using a long, sharp knife, cut the bars into 9 even squares.
Store in a sealed container in the fridge for up to 2 weeks.