Use natural peanut butter for a purer flavor. Chill dough for thicker cookies. The crisscross fork pattern helps cookies bake evenly. Slightly underbake for chewier texture. Measure flour by spooning and leveling for accuracy. Variations include adding chocolate chips, using crunchy peanut butter, or oatmeal. Store leftovers in an airtight container with a slice of bread to maintain softness, or freeze for up to 3 months.