Preheat your oven to 350°F. Line a baking tray with parchment paper. This keeps cookies from sticking. It also makes cleanup very easy after baking.

Take a medium bowl. Add flour, baking soda, and salt. Stir everything well with a spoon. This helps all dry ingredients mix evenly before adding wet ingredients.

In a large bowl, add melted butter, brown sugar, and white sugar. Mix until smooth and creamy. The sugar should fully blend into the butter.

Crack in the eggs one at a time. Mix gently after each egg. Add vanilla extract and stir again until everything looks smooth and glossy.

Slowly add the flour mixture into the wet mixture. Stir with a spatula. Mix only until combined. Do not overmix, or cookies may turn hard.

Fold in chocolate chips gently. Add walnuts if using. Make sure every scoop gets plenty of chocolate. That makes each bite sweet and rich.

Use a cookie scoop or spoon. Place dough balls on the tray. Leave space between each cookie because they spread while baking in the oven.

Bake for 10 to 12 minutes. The edges should look golden. The center may look soft. That is perfect for chewy cookies.

Let cookies rest for five minutes on the tray. Move them to a cooling rack. Enjoy warm with milk for the best taste.