In a large mixing bowl, combine the rolled oats, cocoa powder, chocolate protein powder, ground flaxseed, and a pinch of salt. Stir well to evenly distribute the dry ingredients.

Add the peanut butter, honey or maple syrup, vanilla extract, and dark chocolate chips to the bowl. Mix thoroughly until the ingredients start to come together.

If the mixture is too dry, add 2-3 tablespoons of water gradually until the mixture is sticky enough to hold together when pressed.

Using clean hands, scoop out small portions of the mixture and roll them into balls about 1 inch in diameter.

Place the protein balls on a baking sheet or plate lined with parchment paper.

Refrigerate the protein balls for at least 30 minutes to allow them to firm up.

Store the protein balls in an airtight container in the refrigerator for up to one week, or freeze them for longer storage.