Preheat oven to 350 degrees. Place peanuts on two baking sheets.
Roast peanuts in the oven for 20 minutes or until golden brown. Halfway through baking time, rotate the baking sheets and gently shake them to turn the peanuts.
Remove peanuts from the oven and let cool.
Grind peanuts in the food processor for 5 minutes, stopping after each minute to scrape the sides of the bowl with a spatula.
Add honey and salt. Grind in the food processor an additional 5 minutes, continuing to stop and scrape the bowl after each minute or so.
Store in an airtight jar.
If you like your peanut butter more runny, add 1 tsp of oil at a time when adding the honey and salt, grinding the food processor for at least 2 minutes after each addition. Do not add more than 1 tbsp of oil.