In a large mixing bowl, combine the natural peanut butter and honey (or maple syrup). Using a whisk, blend them together until the mixture is creamy and smooth without any lumps.
Add the pure vanilla extract and salt to the bowl, stirring until incorporated and evenly blended.
Gradually fold in the rolled oats and protein powder. Mix until all dry ingredients are fully combined with the wet mixture, ensuring an even consistency throughout.
Carefully add the dark chocolate chips and chopped nuts to the mixture. Gently fold them in, making sure they are evenly distributed throughout the bulk of the mixture for a well-balanced flavor in every bite.
Prepare an 8x8 inch baking dish by lining it with parchment paper, allowing for easy removal of the bars after setting.
Transfer the energy bar mixture into the lined baking dish. Use a spatula or your clean hands to press the mixture down firmly and evenly, packing it tightly to prevent crumbling later.
Cover the dish with plastic wrap or a lid and refrigerate for a minimum of 1 hour, or until the mixture has firmed up and is easy to cut into bars.
After chilling, carefully lift the mixture out of the dish using the edges of the parchment paper. Place it on a cutting board and cut into bars of your preferred size.
Notes
Arrange the bars in a neat stack or wrap them individually for convenience. Drizzle extra peanut butter on top for added flavor.