Line a standard loaf pan with parchment paper and set it aside.
Combine all of the ingredients in a food processor fitted with an "S" blade, and process until a sticky dough is formed-- it should stick together when pressed between your fingers.
Transfer the dough to the lined pan, and use your hands or a spatula to press the mixture evenly into the bottom of the pan. Place the pan in the fridge or freezer to set until firm, about 2 hours.
Use the parchment paper to easily remove the chilled mixture and slice it into 6 bars. Store them in an airtight container in the fridge for the best shelf life-- they should last at least a month when chilled, though I imagine you'll eat them all before then!
Notes
These bars make an easy snack on the go, and while they get a little softer when not chilled, I actually think their flavor gets better when they come to room temperature-- like a real peanut butter cookie!