Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper.
In a mixing bowl, combine the peanut butter, sugar, and egg. Stir until the mixture is smooth and well-blended.
Scoop tablespoons of the dough and roll them into balls. Place the balls on the prepared baking sheet, spacing them about 2 inches apart.
Press each ball gently with a fork to create a criss-cross pattern on top.
Bake in the preheated oven for 10-12 minutes, or until the edges are lightly golden. Be careful not to overbake.
Allow the cookies to cool on the baking sheet for a few minutes before transferring them to a wire rack to cool completely.