In a large mixing bowl, combine the rolled oats and unsweetened cocoa powder. Use a whisk or a spatula to ensure the two ingredients are evenly blended.
In a small saucepan, set over low heat, add the creamy peanut butter and honey (or maple syrup). Stir continuously until the mixture melts together smoothly and becomes homogenous.
Once melted, remove the saucepan from the heat. Stir in the vanilla extract and salt, mixing until fully combined.
Pour the luscious melted mixture over the oat and cocoa combination in the mixing bowl. Using a spatula, fold the ingredients together until every oat and cocoa particle is thoroughly coated with the chocolatey mixture.
Carefully fold in the mini chocolate chips and any optional chopped nuts, ensuring they're evenly distributed throughout the mixture for an added texture and flavor.
Prepare an 8x8 inch baking dish by lining it with parchment paper, making sure it overlaps the edges for easy removal later. Transfer the mixture into the prepared dish, pressing it down firmly and evenly with a spatula or your hands until it’s compact and smooth on the surface.
Refrigerate the bars for at least 2 hours to allow them to set and become firm. This step is vital for achieving the right texture.
Once the bars are fully chilled and set, carefully lift them out of the dish using the parchment paper overhang. Use a sharp knife to cut them into squares or rectangles as desired.
Notes
Arrange the bars on a decorative platter, lightly dust them with cocoa powder, and sprinkle a few extra chocolate chips on top for a delightful finishing touch that enhances their visual appeal.