Toast the nuts in the oven or in a skillet until slightly browned. To toast in an oven, spread the nuts in a single layer in a shallow pan and bake at 350F for 10 minutes, stirring the nuts occasionally so they brown evenly. To toast on top of the stove, place the nuts in a skillet and cook them over medium-high heat, stirring or shaking the pan constantly so they brown evenly. Be sure that you turn all the nuts over frequently as they cook or they will scorch. A teaspoonful of oil helps distribute the heat and keep everything moving, resulting in more even browning.

Transfer the toasted nuts to a food processor and process 1 minute. Stop the machine, scrape the sides and bottom of the bowl thoroughly, and continue processing another minute or two, scraping the bowl occasionally. Eventually the sound will change as the mixture changes from finely chopped nuts to a thick, smooth mixture that clings to the sides of the bowl. Have patience; this can take two or three minutes. If the nuts refuse to form a butter, add a little oil through the feed tube (hazelnuts usually require some oil). When the blade spins free, scrape down the mixture one more time and blend a few seconds more. Taste the butter and add a little salt if desired; process briefly to stir it in. Store nut butters tightly covered, at room temperature or refrigerated, and use within a week or so.

This recipe is from The Art Of The Sandwich by Jay Harlow.