I actually made this back in February 2015 during a camp trip on the California coast. It's really simple but I finally took some photos of my youngest wearing it. While packing for our camp trip, I found it and thought I'd throw it on him for a photo :) He actually wasn't as resistant as he has been recently!
Yarn - Lion Brand Hometown Chunky yarn (I don't remember but I think I used more than one ball)
Chain 48 (or any even number of stitches for the size you want the circumference of the cowl)
Join with a slip stitch to the beginning chain, careful not to twist the stitches.
Round 1: Chain 1, 1 single crochet into every stitch all the way around, join with a slip stitch to beginning chain 1
Round 2: Chain 4 (counts as a double crochet & a chain 1). skip one stitch, *1 double crochet into the next, chain 1, skip a stitch. Repeat from * all the way around. Join into the 3rd chain in the beginning chain 4 (the 4th chain is your chain 1 space)
Repeats round 1 and 2 until desired height is reached. I did a total of 9 rounds (5 single crochets & 4 double crochet rounds).
Single crochet the final round.