I found a quick and easy cold porcelain recipe at the Deviant Art Forum, posted by beatus-vir. This is a microwave recipe and is made from just glue, cornrstarch & lemon. She also shows us how to add color to the cold porcelain paste using oil colors, pastel chalks, acrylic paints and watercolors.
Click here for recipe and mixing tutorial!
(Note: Tutorial is written in both Spanish and English. I feel pretty sure that where it says "white rubber", it really means "white vinyl glue" ....that's what happens when computers translate! LOL)