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Lay parchment paper across the baking sheet or dish. Shake and drip dry. Note that if you feel the seeds are clean enough, you may skip this step (although, see Tips below for a suggestion about reducing phytic acid). Place in the oven. They're ready when they've uniformly turned a light brown.
Preheat the oven to 170ºC/340ºF. Rinse the sesame seeds in a fine colander. Arrange the seeds across the baking sheet. Bake for about 10-15 minutes, stirring frequently to prevent burning. Remove from the oven and let cool completely.