I also kind of made this up but was inspired by Stoller's SnB

I saw something that looked like this in Stitch n' Bitch by Stoller, but I revised it so it's done from the top. This is easier for me. Someone asked me how so here is what I told her (btw, I think I changed it enough so that it's ok to print):
Cast on 9 stitches onto one DPN
Transfer stitches to 3 DPN
Knit first round, increasing every stitch by knitting into front and back of each stitch (bar increase) until you get to the last stitch
Knit last stitch together with first stitch on next needle to join round(16 stitches total).
Knit one round even
Next row, inc 1, k1, inc1, k1 all the way around
Knit one round even
inc 1 k2, inc 1 k2 all the way around
Knit one round even.
Keep going like this increasing around until the hat is the desired circumference to fit the baby in question.
Knit even until long enough to cover the ears + 1-2" for the roll and cast off. It's stockinette, it'll roll on its own.
Go back to hole at top where you started with 8 stitches.
Pick up and knit 4 stitches evenly around. Do an I-cord for about 4" or until it's long enough to knot. Break the yarn and draw through the stitches to fasten off.
Ta-da!