I'm a young Scotsman who recently has developed a higher and higher tolerance for spice in a variety of foods. I love Srirasha on most things edible, and enjoy trying out new hot sauces wherever they're available. Sadly though, I have found when ordering out at Thai/Chinese places that even if I order something that states it as a spicy dish that the ""zing" just hasn't quite been there. Sometimes its corrected when I literally ask "What is the spiciest thing you have?" but even then I have found that the waitstaff have cut back on the spice (assuming) that since I'm Caucasian I can't handle REAL spice. This was recently proven when I went out with a friend who is full Thai, being born there and fluently speaks Thai. She ordered the EXACT same dish for both of us, and when they came to the table, hers was noticeably spicier (and thus more delicious) than mine.
What would be your suggestion on explaining to the staff that I don't want to be judged by my skin colour on how well they think I can tolerate spice levels? I asked my friend and she said some people might be offended if I only learned how to say "extra spicy" in Thai etc.