Set up the food processor.
Toast the sesame seeds into a dry frypan on medium until fragrant and you see just a few starting to turn light brown. Immediately pour them into the food processor so they don't brown.
Process the seeds while slowly adding the olive oil. Process the mixture for several minutes until it becomes a paste.
Add the chickpeas to the food processor along with the lemon juice and salt and process until light and fluffy, stopping occasionally to scrape down the sides. To make it more creamy, add some of the reserved cooking liquid. To make it fluffy as well, add cold water. Process for at least 5 minutes to make the hummus a smooth texture. It will thicken as it cools.
At this point, other flavorings can be added - more lemon juice, vinegar, garlic olive oil, spices, herbs, etc.
Traditionally served warm, it is also good cold. Drizzle with olive oil or homemade garlic olive oil. Add fresh herbs, salt and pepper, or any of a number of spices or seeds.