Spread the roasted peanuts on a tray and quickly pick out any super‑dark or burnt ones so they don’t make the peanut butter powder taste bitter. If your peanuts have skins, rub them in a clean kitchen towel to remove as many skins as possible; this helps create a smoother, less gritty powder.

Add the prepped peanuts to a high‑speed blender or good food processor. Pulse in short bursts at first, then process continuously. The peanuts will go from coarse crumbs to sandy meal, then to a thick paste similar to natural peanut butter. Stop to scrape down the sides as needed. This stage usually takes 2–4 minutes, depending on your machine.

Scoop the peanut paste into a fine‑mesh nut milk bag, several layers of cheesecloth, or a very thin clean cotton kitchen towel. Gather the cloth and twist and squeeze firmly over a bowl. Peanut oil will start to drip out; continue pressing until the paste feels quite firm and dry. This step removes much of the fat and is key for a lighter peanut butter powder.

Transfer the pressed peanut “cake” back into your blender or food processor. Break it into smaller chunks with your hands so it’s easier to process. Blend again until the mixture turns into a fine, crumbly meal. It should no longer form a paste, since most of the oil has been removed.

Sprinkle in the fine sea salt, coconut sugar or light brown sugar (if using), and cornstarch or arrowroot starch. Pulse several times, then process for about 30–60 seconds so everything is evenly distributed. Taste a pinch of the mixture and adjust salt and sweetness now, while it’s still in the processor.

Continue processing until the texture resembles a very fine flour. In a high‑speed blender this may take 30–45 seconds; in a food processor it can take a couple of minutes. If the mixture clumps on the sides, stop and fluff it with a fork or spatula, then resume processing. The powder is ready when it feels light and powdery between your fingers.

For an ultra‑smooth peanut butter powder, pass the mixture through a fine‑mesh sieve into a bowl. Any larger bits left in the sieve can go back into the blender or processor for another round. This optional step helps the powder dissolve more easily in smoothies, sauces, and baking recipes.

Spread or leave the peanut butter powder in the bowl and let it sit at room temperature for 20–30 minutes to cool completely and release any residual warmth from blending. Once cool, transfer to an airtight glass jar or container and label with the date. Store in a cool, dark pantry, the refrigerator, or freezer depending on how long you plan to keep it.

To turn the powder into a spread, stir 2 tablespoons peanut butter powder with 1½–2 tablespoons water in a small bowl until smooth. Add the water gradually until you reach your desired consistency. Adjust with a pinch more salt or a little extra sweetener if desired.