Preheat the oven to 325°F. Lightly grease (or line with parchment) two baking sheets.
In a medium-sized bowl, cream together the butter, sugars, corn syrup, baking soda, salt, and vanilla. Add the eggs one at a time, beating well after each addition. Add the peanut butter, beating until the mixture is light and fluffy. Stir in the flour.
Drop the dough by the tablespoonful onto the prepared baking sheets. Bake the cookies for 15 minutes, until they?re a light golden brown around the edges. Don?t overbake or they?ll be crisp, not soft. Remove them from the oven and transfer to a rack to co