What's the difference between Red and Panang curry? I love Panang curry and Thai food in general. However, whenever I try to make  curry at home it always comes out as indistinguishable from Red curry. What's the distinction between these two dishes? I feel like I'm probably just missing one or two ingredients that make the difference, but my trusted recipe books and google haven't been of much use.
I have just looked in the book "Thai Food" (by David Thompson).

Both are very similar. The main difference I can see is that there are souring agents in the red curry (fish sauce and shrimp paste). These are absent in the panaeng which has peanuts as a major ingredient in the paste (and nutmeg).

The panaeng is also usually made with beef which is simmered in count milk until tender.