**KitchenAid’s standard stand mixer attachments aren’t a good choice for making peanut butter.** The two grinders have different limitations:

- **Grain mill:** Don’t use it for peanuts. KitchenAid explicitly warns that their high oil content can damage the grinding mechanism. [KitchenAid’s grain mill guidance](https://producthelp.kitchenaid.com/Countertop_Appliances/Stand_Mixer_Attachments/Pasta_and_Grains/Grain_Mill/Grain_Mill_Tips)
- **Food/meat grinder:** It can grind nuts, but its blade and perforated plates produce ground pieces rather than the very fine, creamy paste you want. I wouldn’t buy one for peanut butter. [KitchenAid’s grinding guidance](https://www.kitchenaid.com/countertop-appliances/pinch-of-help/what-to-use-instead-of-a-food-processor)

The hopper machine at your merchant is likely a dedicated nut butter mill. Its resemblance to a meat grinder doesn’t mean the grinding mechanism is equivalent.

For home use, **a standalone food processor with an S-shaped blade is the practical option**. Process roasted, shelled peanuts until they progress from crumbs to a clump and then a creamy paste, stopping to scrape the bowl as needed. KitchenAid recommends this method itself. Its stand mixer *food processor attachment* only slices, shreds, juliennes or dices; it lacks the blade needed for this task. [Peanut butter instructions](https://www.kitchenaid.com/countertop-appliances/pinch-of-help/how-to-make-peanut-butter-in-food-processor), [attachment functions](https://www.kitchenaid.co.uk/mixer-attachments/859711695790/food-processor-for-mixer-5ksm2fpa-silver)