Preheat the oven to 300°F (150°C). Line 2 baking sheets with parchment.

In a medium bowl, whisk the egg with a fork. Add the peanut butter and sugar, mixing until smooth. Stir in the chocolate chips.

Roll 1 tablespoon (15 mL) dough into a ball. Place 2 tablespoons (30 mL) sugar in a small bowl. Dip one side of the ball in the sugar and place with the sugared side up on the prepared pan. Repeat with the remaining dough, spacing 2 inches (5 cm) apart.

Using the tines of a fork to make a crisscross pattern, flatten each cookie to about 1⁄2 inch (1 cm) thick.

Bake, one sheet at a time, on the middle rack of the preheated oven until the edges are set, about 20 minutes.

Let cool on the baking sheet for 5 minutes before transferring the cookies to a wire rack to cool completely.