Preheat the oven to 350F and line a baking sheet with parchment paper, or a reusable silicone baking mat.
In a medium bowl, cream the butter and maple syrup for 30-60 seconds until smooth. Stir in the peanut butter, egg and vanilla, until smooth.
Fold in the flour, baking soda and salt until well combined and there’s no flour visible, but don’t overmix.
Cover and transfer to the fridge to chill for 30 minutes, for the butters to firm up.
Roll out 2 tablespoons of the dough at a time into balls and place on the lined baking sheet.
Press a chocolate chunk into the middle of each ball and flatten slightly.
Transfer to the oven to bake for 10 minutes, until the tops are firm and bottoms are just slightly golden.
Let the cookies cool on the baking sheet for 5 minutes before transferring to a cooling rack to cool completely and enjoy.
Store in an airtight container at room temperature for 3 days or for up to 1 month in the freezer.