you just toast 1-3 cups of sesame seeds for a few minutes until they start to turn golden brown. Then you remove them from the heat and allow them to cool before processing them into a paste/butter, either using a high speed blender or a food processor. I've found that I don't need to add any extra oil when I make tahini in my Vitamix. However, if you have an older blender or a less powerful food processor, you can always add in some oil towards the end to achieve a runnier, smoother tahini.