Preheat the oven to 400 F. Lightly coat a baking dish with cooking spray.
In a heavy frying pan, add the sesame seeds in a single layer. Over low heat, cook the seeds, stirring constantly until they look golden and give off a noticeably toasty aroma, about 1 to 2 minutes. Remove the seeds from the pan to cool.
In a bowl, add the coriander, cayenne pepper, celery seed, minced onion, cumin, cinnamon, sesame oil and toasted sesame seeds. Stir to mix evenly.
Place the pork tenderloin in the prepared baking dish. Rub the spices on both sides of the pork pieces. Bake until no longer pink, about 15 minutes. Or bake until a meat thermometer reaches 165 F (medium) or 170 F (well-done).
Transfer the pork tenderloin to warmed plates. Serve immediately.