If you are really interested in learning to cook Thai food, this is the course you want to take. You choose six different dishes to make out of a total of around 50 dishes; you also get a cookbook with ALL the recipes plus several that you can't do in the one-day course. The recipes are very authentic, and they all work; it would be worth the price alone just for the recipe book. The menu is listed on their website (below).
The groups are kept to a maximum size of about 6 people, but the advantage of having a few other people around is that you'll all be making completely different dishes, so you can get a feel for the other things in your book that you didn't make.
The other outstanding thing about this school is the teacher, Vannee -- she walks the line perfectly between letting you do everything yourself and making sure you don't make a mistake. We had 4 people constantly cooking the whole time, and nothing got burned or left out or done too early or too late.
They also offer longer courses at a discount, where you can learn to do more of the dishes that you didn't do on your first day. I intend to return when I've got more time and do a week's course.
Also, you get a discount if you call or email ahead rather than doing it through a guesthouse or travel agent; their website is at http://www.chiangmai1.com/restaurants/classichomecooking.shtml
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