Follow the steps in order for the best result.
In a spacious mixing bowl, combine the softened unsalted butter, light brown sugar, granulated sugar, aromatic vanilla extract, and salt. Use a sturdy spoon to vigorously beat the mixture until it becomes light and fluffy in texture.
Next, incorporate the large egg and baking soda into the creamed mixture, beating thoroughly until well combined.
Gently fold in the all-purpose flour, along with the coarsely chopped walnuts and generous chocolate chunks, until just combined. Be careful not to overmix.
Scoop the dough into a separate bowl, cover it tightly, and refrigerate for a minimum of four hours, or ideally, overnight, until the dough is firm and chilled.
Once ready to bake, preheat your oven to 350°F (175°C).
For each cookie, scoop out approximately two to three tablespoons of the chilled dough. Roll it into a uniform ball and arrange these dough balls onto baking sheets that have been lightly greased with vegetable shortening, ensuring adequate spacing between each.
Bake for 10 to 12 minutes, or until the edges are golden and the centers spring back gently when lightly touched. Avoid overbaking for a chewier texture.
Allow the freshly baked cookies to cool on the baking sheets for two minutes before carefully transferring them to a layer of paper towels for another two minutes of cooling. Finally, move them to wire racks to cool completely, ensuring a crispier bottom.