When you say authentic, do you mean that they have all or most of the same vegetables as they do in Thailand? Small green Thai eggplant, pea eggplant, morning glory, all the different peppers, fresh holy basil, proper mushrooms, etc, etc? I have yet to find a Thai restaurant in the US that has anywhere near the variety of produce to be even remotely 'authentic'. Carrots, broccoli, bell peppers, zucchini and so forth is what I normally find here, and doesn't work for me at all.