Preheat the oven to 350°F (176°C). Line a large baking sheet with parchment paper and set aside.
In a stand mixer, mix the peanut butter, sugars, egg, and baking soda on medium speed until combined. Fold in the chocolate using a spatula.
Roll the mixture into 1-inch (2.5 cm) balls and place them on the baking sheet, at least 2 inches (5 cm) apart.
Bake for 12 minutes, or until lightly golden. Remove from the oven and allow to rest on the baking sheet for about 5 minutes before transferring to a rack to cool completely.
Notes
Because the dough has so much chocolate, try pressing the dough together to form the balls rather than rolling. It works better.