Duh! Of course beer. The only problem is that I detest beer and everything about it, but it would be the way to go. Aren't beer soaps a bit brownish? I'll have to go look. I haven't seen any cheese FO's, especially deep fried.
Pilar, I think there is a video on the Great Cakes Soapworks blog page, but it's pretty easy. In a small container (paper cup or plastic cup), mix perhaps a couple mls of oil (I use Olive Oil) and a small bit of the mica you want- maybe 1/8 tsp. Mix it well. It should not be thick or pasty but very fluid, like the oil alone. Add more oil or mica as needed to get a nice solid color but keeping it nice and fluid. A little goes a long way. After you've poured your soap, drizzle the mica oil on top, using one or several colors. It usually comes out in drops. Swirl with a straw, skewer or whatever you usually use, just on the surface. For these, I had drops of oils scattered over the surface, perhaps 2-3 drops every 4 square centimeters.
I'm glad they had the challenge. I haven't done this for some time and it gives an excellent effect.
I will post cut pics but I'm trying really hard to be patient. I didn't gel so I'm waiting for it to firm up more before I unmold it. I have zero patience and have been freezing and unmolding, then cutting my soap too early, so the edge crumble. Oh, hell, I'll go pop it in the freezer and see if I can't get a pic tonight. I'm a geller in general because of my impatience.