If you can read Thai, and spend enough time in northern Thailand, eventually you'll start to see the word luu on restaurant signs just about everywhere. I had a vague notion of this northern dish, knew it was something blood-related, and noticed that it always seemed to be found to be at restaurants that serve the famous northern-style laap. But other than this, I had never seen or sampled it. Recently in Phrae, I was able to get a crash course in luu.
It is indeed a blood dish, raw blood being the primary ingredient. The owner of the shop that was recommended to me explained that the blood must be purchased very fresh. It tends to coagulate somewhat nonetheless, he told me, so he still has to run it through a blender when he gets back home. He then adds eggs (raw) and lemongrass leaves (not the stalks, just the leaves; he made this very clear). He then kneads this mixture together by hand for about 20 minutes, before pouring it through a cloth strainer and storing the strained blood on ice. I forgot to ask why eggs were added, but I suspect the lemongrass leaves play some role in preventing the blood from coagulating.
To prepare the dish, a ladleful of the blood is poured into a bowl and mixed with a chili paste (that contains, among other things, makhwaen, the dried spice that's ubiquitous in northern Thailand), some chopped cilantro, and a pinch of salt and MSG:
As shown at the top of this post, the blood mixture is served with a mixture of crispy fried noodles, deep-fried kaffir lime leaves, deep-fried sections of large intestine ('Very difficult to prepare,' explained the owner. 'They have to be washed very well, then boiled, then deep-fried. It takes a long time.'), deep-fried pork rinds and a bit of the liquid from a jar of pickled garlic. To eat it, the blood is poured over the noodle mixture (he said that some people prefer bits of boiled or raw pork fat in place of the noodles), and mixed thoroughly:
I sampled a bit of it, and honestly, it was quite tasty. This guy has created an amazing homemade chili paste, and it was this flavour that came through most clearly. The texture was crunchy, mostly due to the deep-fried intestines and pork rinds. The colour, a brilliant, deep red, was for me the most disturbing part. I was alone in my tasting though; 'I've been making this dish for 22 years,' the owner told me, 'and I've never eaten it. I don't like to eat raw things.' I asked how he could make it without tasting. 'Experience,' he replied.
Other dishes served at his restaurant included, and I'm not making this up, grilled cow teats ('Very good, better than other kinds of beef') and aep orn muu, banana leaf packets of grilled pork brains.
Welcome to northern Thailand.