Making your own peanut butter is extremely easy
Dump some peanuts into a food processor. Turn it on and wait until the peanuts are peanut butter.
Really, that's it. At a certain point the ground up peanuts become a doughy mass getting slowly pushed around by the blade, so I used to add some peanut oil in the hope of making it smoother, but I have learned to just be patient and let the blade do its work. Well, maybe I stop the food processor when this happens, push the doughy mass down towards the blades, then start it up again, but that's all I do.
For peanuts I use the 16-ounce lightly salted store brand.
Lately, I've really been enjoying peanut butter sandwiches with sriracha!