In a medium bowl, stir together the maple syrup, nut butter and vanilla until well combined.
Mix in the salt and protein powder. Add water as needed starting with 1 tablespoon and gradually adding more. You want the batter to be quite thick so only add enough water to be able to thoroughly combine it.
Line a 9x4 inchloaf pan (9x5 or 8x4 should work as well) with parchment or a silicone liner. Pour the batter into the pan and press it firmly into an even layer.
Allow the bars to set for a minimum of 2 hours in the refrigerator or 30 minutes in the freezer.
Use the liner to lift the bars onto a cutting board and slice into your desired shape and size. Store for later or enjoy!
Notes
LeftoversPlace your cookie dough protein bars in an airtight container at room temperature for up to 3 days, in the refrigerator for up to 1 week or freeze for up to 3 months. *I recommend keeping them chilled for best texture.