I found the pattern on Ravelry (Sarah Moore's Snow Day socks which you can find here). I used Rico Essentials Soft Merino Aran, of which I bought three balls but used just over two. They are a softer green than the photo suggests.
In contrast to all the other socks I've knitted these were worked from the toe up, which I think I now prefer. The heel was a doddle to turn.
I love the way they slouch round the ankle. So much so that I think I may knit another pair for myself!