I wrote a (not super-technical) pattern so I can replicate it:
Materials: One skein Zen Serenity Chunky, size 13 needles, yarn needle, pompom making device of your choice.
CO 54 in the round, k1p2 around for 24 rows
k2tog p1 k1 p2 around 1 row (48 st)
k1 p1 k1 p2 two rows
k1 p1 k2tog around 1 row (42 st)
k1 p1 two rows
k2tog k1 p1 around 1 row (36 st)
k2 p1 one row
k1 k2tog around 1 row (30 st)
k one row
k2tog around one row (15 st)
k2tog 3x, k1, ktog 4x (8 st)
Pull yarn through all st, secure.
Roll 1.5" brim 2x, sew in place with yarn loosely - make sure hat stretches to full width!
Make pompom with remaining yarn, attach snugly to hat.
Weave in all ends, block if desired.