Painted on pencil line?

[abc]

Look at the shape of it though. I don't think that's cocoa powder all by itself because parts of it outlining the drops are too thick and have corners on them. That looks more like how batter moves and responds to a drop than how powder does. Maybe she will tell you how she does it but I would guess that it's cocoa powder in small amount of batter. Even powder in oil seems unlikely to stay in that shape.

If you click the "this" in the post with the picture, it takes you right to her blog.

ETA:

I was going for thin pencil lines of darker color between the yellow and brick. I used cocoa powder because it gives a soft yet dark enough brown which would enhance the yellow and brick by making them look brighter and would also set off the swirls.

To achieve the pencil lines I had to lay some cocoa powder colored batter before making each “drop” so it took a little longer than usual and part of the cocoa colored batter was pushed to the sides of the soap.

 

[kchaystack]

Yes! How was that achieved??

From her blog :

To achieve the pencil lines I had to lay some cocoa powder colored batter before making each “drop” so it took a little longer than usual and part of the cocoa colored batter was pushed to the sides of the soap.

Looks like she did a thin, thin layer of soap with cocoa powder as Obsidian said.

 

[coffeetime]

I think I will try keeping back about 2tbsp of my liquid oils, then adding that to a couple of table spoons of soap batter with my colourant and use that for my line. Then a thin-ish drop swirl.