Place the sesame seeds in a medium or large skillet. Set on the stovetop over medium heat and toast, stirring and/or swirling the pan periodically, until golden brown and fragrant, 8-10 minutes. Monitor closely to avoid burning the seeds, but also keep in mind the the more you toast them, the less bitter the tahini will be.
Remove from the heat and allow to cool for a few minutes, then transfer to a food processor along with the oil and salt, if using.
Pulse several times to distribute the oil, then turn the machine on and let it run until the tahini is smooth, 3-5 minutes, scraping the bowl down at least once mid-process.
Transfer to an airtight container and store in the refrigerator for up to one month. Yields approximately 1 cup.
Notes
Grapeseed oil is my top pick when it comes to a neutral-flavored oil for recipes. Safflower oil is also a good choice. Some people recommend canola, which I think has a synthetic flavor. If you’re thinking about using canola oil in tahini, I recommend first tasting a bit so you can decide for yourself. Peanut oil has a mild flavor of roasted peanuts, but that will work in tahini.I purchased sesame seeds online in bulk to save money. Some stores also carry them in the bulk goods aisle.