As a follow up to my previous post about Chocolate Fudge Overload Pie, I found out why chocolate seizes and why adding more water is a viable solution to recover. It's all about the emulsion of course. The short answer is that chocolate is a delicate balance between fat and water. When heated, it's easy to disrupt that balance with the addition of just a tiny bit of water and the sugar will crystallize. By adding more water the emulsion is reversed and balance is restored.