In a large bowl, stir together the rolled oats, peanut butter, honey, ground flaxseed, chocolate chips, and vanilla extract until thoroughly combined.

Cover the bowl and refrigerate for 30 minutes to allow the mixture to set, making it easier to handle.

Remove from the refrigerator and scoop approximately one tablespoon of the mixture at a time.

Roll each portion between your palms to form a smooth ball approximately 1 inch in diameter.

Place the finished balls on a parchment-lined tray or directly into an airtight container.

Store in the refrigerator for up to one week or freeze for longer preservation.