Preheat oven to 350 degrees. Line 2 baking sheets with a silicone baking mat or parchment paper.
In a mixing bowl, using a large spoon, mix together peanut butter, granulated sugar, light brown sugar, egg and baking soda until well blended.
Stir in chocolate chips.
Drop dough by the rounded tablespoonfuls (about 1 1/2 Tbsp each) onto prepared baking sheets, spacing cookies 2-inches apart.
Flatten each slightly. Bake one sheet at a time in preheated oven 10 - 12 minutes.
Store cookies in a single layer in an airtight container, they are somewhat delicate so don't just toss them into a bag or they can break apart.