In a food processor or blender, combine the nuts, 2 tablespoons of the oil, the salt, and the sugar, if desired. Process on high speed for 30 seconds. Scrape down the sides with a rubber spatula and process to desired smoothness, adding more oil, 1 teaspoon at a time, if a smoother butter is desired. Adjust the seasoning, to taste.
Transfer to a bowl to use as a dip, spread, or in other recipes, or place in an airtight container and refrigerate until ready to use.