Preheat your oven to 350°F and line two baking sheets with parchment paper or silicone baking mats.

In a large mixing bowl (or the bowl of a stand mixer fitted with the paddle attachment), cream together the softened butter, granulated sugar, and brown sugar until light and fluffy– about 2 minutes. 

Add the egg and vanilla extract and mix to combine. 

In a separate bowl, whisk together the flour, baking soda, and salt. Add the dry ingredients to the wet and mix just until combined– you don’t want to overmix! 

Fold in the chocolate chips and chopped walnuts. 

Scoop out 2-tablespoon sized portions and place them at least 2” apart on the prepared baking sheets. Press the cookie balls into ½” thick discs. 

Bake for 10-12  minutes, or until the edges are lightly golden are just set. The centers will still be soft but they will firm up as they sit– for chewy cookies, make sure not to overbake! 

Allow the cookies to cool on the baking sheet for 5 minutes, then transfer them to a wire rack to cool completely.

Store any leftover cookies in an airtight container at room temperature for up to five days.