In a medium bowl, mix peanut butter and honey/maple syrup until smooth.
Add vanilla extract and cocoa powder (if using), stirring until combined.
Gradually fold in the oats and salt until evenly mixed.
Line a baking sheet with parchment paper.
Using a tablespoon, scoop the mixture and form into balls.
Flatten each ball slightly with the back of the spoon.
Place the cookies on the prepared baking sheet.
Refrigerate for at least 30 minutes to firm up.
Once set, remove from the fridge and enjoy!
Store any leftovers in an airtight container.