Bulky yarns are in, but weight is out. Your answer to this: Cortina. Cortina is a modern marvel of yarn, created with an air-infused nylon core that is encased in fine Merino wool, making it unimaginably lightweight while still having that great wool feeling.

The voluminosity of the yarn allows you to knit complex stitch patterns quickly at 2 ½ stitches per inch, without adding extra weight to your garment. This yarn has 55 yards per 50 gram ball. It knits up on US 11+ needles yielding 1.5-2.75 stitches per inch.