Preheat your oven to 180°C (350°F) and line a baking sheet with parchment paper.
In a large mixing bowl, cream together the softened butter, peanut butter, and brown sugar until the mixture looks fluffy and is just beginning to lighten in color, about 2 minutes.
Add the egg and vanilla extract to the creamed mixture. Beat until smooth and well combined, filling the bowl with a fragrant, buttery aroma.
In a separate bowl, whisk together the all-purpose flour and baking soda. Gradually add these dry ingredients into the wet mixture, mixing just until the flour is incorporated—be careful not to overmix, as this can toughen the cookies.
Fold in the chocolate chips with a spatula or spoon, ensuring they're evenly distributed throughout the dough. The dough will be thick and slightly sticky, with chocolate chips peeking through.
Using a tablespoon or cookie scoop, portion out rounded scoops of dough onto the prepared baking sheet, spacing them about 2 inches apart to give room for spreading.
Gently flatten each dough ball with the back of a fork or your fingers—a slight press helps them bake evenly and creates a more uniform appearance.
Bake in the preheated oven for about 10-12 minutes, or until the edges turn a beautiful golden brown and the centers still look soft but set. You'll start to smell the rich aroma of baking peanut butter and melting chocolate.
Remove the baking sheet from the oven and let the cookies rest for 5 minutes; they will continue to firm up as they cool while maintaining their chewy centers.
Transfer the cookies to a wire rack to cool completely, or enjoy them warm with gooey chocolate pockets in every bite—either way, they're irresistibly delicious.