1. Preparing Your Ingredients

Preheat your oven to 325°F (163°C) and gather all your ingredients. Ensure your butter is softened to room temperature for easy mixing. If you’re adding walnuts, chop them into small, bite-sized pieces.

2. Mixing the Dough

In a large mixing bowl, combine the salted butter, light brown sugar, and granulated sugar. Use a stand mixer, hand mixer, or a sturdy wooden spoon to mix until the mixture is light and creamy. This process should take about 2-3 minutes. Next, add the milk, vanilla extract, and egg. Mix again until everything is fully combined. Be careful not to overmix – stop as soon as the ingredients are incorporated.

3. Sifting and Adding Dry Ingredients

In a separate bowl, sift together the all-purpose flour, kosher salt, and baking soda. Gradually add the dry ingredients to the wet mixture, one cup at a time, mixing gently after each addition. This will prevent the dough from becoming too dense. Be mindful to mix only until the flour is fully integrated into the dough to avoid overmixing.

4. Incorporating Chocolate Chips and Walnuts

By hand, fold in the milk chocolate chips and walnuts (if using). Ensure they are evenly distributed throughout the dough.

5. Shaping the Cookies

Using a tablespoon, scoop out the dough and roll it into balls with your hands. Place each dough ball onto an ungreased cookie sheet. If the dough feels sticky, add an extra ¼ cup of all-purpose flour, mixing just until combined.

6. Baking the Cookies

Place the cookies in the preheated oven and bake for 8-11 minutes. They might look slightly undercooked, but once the shine has disappeared from the dough, they are ready. Remember, the cookies should not be browned on top. If they seem underdone, bake for an additional 1-2 minutes, especially if you are baking at a higher altitude.

7. Cooling the Cookies

Let the cookies rest on the baking sheet for about 10 minutes before transferring them to a wire rack to cool completely. This helps them firm up and prevents them from breaking apart.