Knitted cog?

I’m making a pair of steampunk themed Converse style slipper socks for a friend’s Christmas present, but does anyone have any ideas as to how I could knit a flat ring, fairly small in size, as the base for a knitted cog ? (Converse have the flat white circles with a star on the outside, I just want to have a cog or gear there instead)
Would doing a flat circle on DPNs, but initially casting on with more stitches work?

I’m thinking I could pick stitches up around the outside for the ‘teeth’.

Sounds like a fun present. Here’s instructions for several configurations of flat circles:

Thanks, I might be able to adapt the Pi one :slight_smile: