The body of the bag is knitted from one corner starting with a 1-stitch cast-on and increasing 1 stitch at each end of the knit row. A perfect square in garter stitch.

The yarn’s colour is beautiful but I wish it was softer.

I’ll write up the pattern soon. :) Let me know if you want to know when the pattern is available.

Update:
Pattern has been written up. Please see right side bar for About This Pattern.