01 - Preheat oven to 350°F. Line a baking sheet with parchment paper and set aside.
02 - In a large mixing bowl, beat the softened butter, granulated sugar, and brown sugar together using an electric mixer on medium speed until pale, light, and fluffy, about 2 to 3 minutes.
03 - Add the egg and vanilla extract to the butter mixture. Beat on medium speed until fully incorporated and the mixture appears smooth.
04 - In a separate medium bowl, whisk together the all-purpose flour, baking soda, and salt until evenly distributed.
05 - Gradually add the dry ingredient mixture to the wet ingredients, mixing on low speed until just combined. Avoid overmixing to keep the cookies tender.
06 - Divide the dough into 16 equal portions. Flatten each portion in the palm of your hand, place one piece of chocolate in the center, and fold the dough around it. Gently roll between your palms to form a smooth ball, ensuring the chocolate is completely sealed inside.
07 - Place the filled cookie dough balls on the prepared baking sheet, spacing them about 2 inches apart to allow for spreading.
08 - Bake for 10 to 12 minutes, until the edges are set and lightly golden while the centers still appear soft and slightly underbaked.
09 - Allow the cookies to rest on the baking sheet for 5 minutes, then transfer to a wire rack to cool completely. Serve warm for an extra gooey center.