I liked the look of Tarboosh by Purl Up, Knit but missed the free pattern offer, and being a bit of a frugalist, I couldn’t justify paying $6 for a simple cable pattern, so I had a go at reverse-engineering it.

It was simple -

CO 81sts (multiple of 9) Join to work in the round.
Work 8 rounds K6, P3 (sets pattern)
Next rnd: (K3 wrapping yarn round needle twice, K3, P3) repeat to end of rnd.
Next rnd: (Sl 3 sts, dropping extra wrap, sl next 3 sts, pass first 3 sts over & back onto left needle, slip second 3 sts back to left needle, K6, P3) repeat to end of round.
Repeat these 10 rounds until hat is long enough.

** I found it really easy using a crochet hook for the slip stitch section. Slip sts onto crochet hook, then use tip of left needle to lift sts over, hooking second set through**

Decrease for top -
Work 1 round in K6, P3 pattern (81sts)
Next rnd: (K6, P1, P2tog) rep around (72sts)
Next rnd: (K6, P2) rep around (72sts)
Next rnd: (K2tog tbl, K2, K2tog, P2) rep around (54sts)
Next rnd: (K4, P2) rep around but finish last repeat with P1 (54sts)
Next rnd: (K2tog, K2, K2tog tbl) rep around (36sts)
Next rnd: K2tog around (18sts)
Next rnd: K2tog around (9sts)
Break off yarn leaving a 6” tail and thread through remaining sts, pull tight. Sew in ends

Finished hat will fit 19”/48cm head comfortably; height 8”/20cm.
Adding another cable/rib will increase size by 2”/5cm.