Preaheat oven to 325 F
Cream sugar and peanut butter until smooth.
Mix in egg until fully incorporated.
Roll into 1" balls, placed at least 1" apart on a baking sheet.
Flatten with a fork vertically and horizontally so the tines form a grid pattern.
Bake 15 minutes (until firm).
Let cool on the sheet for 5 minutes before transferring to a cooling rack.