Preheat oven to 375°F375 °F degrees with the rack in the middle. Line 2 baking sheets with parchment paper.

Dry ingredients: First, combine 1 3/4 Cups all-purpose flour (fluffed, gently scooped, scraped to level) and 1/2 tsp baking soda and whisk to combine, set aside.

Brown the butter: In a skillet, melt and then brown 10 tablespoons of unsalted butter for about 2-3 minutes over medium high heat.

You want a slight golden color, not dark amber color. The butter will start to smell like toffee. Watch it, as it burns easy.

Transfer to a heatproof bowl or a mixer bowl and add the remaining 4 tablespoons of butter. Whisk until the butter is melted.

Add sugars: Add 1/2 Cups granulated white sugar, 3/4 Cups packed dark brown sugar,1 tsp kosher salt and 2 tsp vanilla extract and whisk until smooth, about 30 seconds.

Let the mixture sit for 3 minutes, then whisk it again. Repeat 3 times (if you're in a hurry, you can skip this step). The goal is to cool the mixture enough before adding the eggs in the next step, so they don't cook.

Add eggs: Next, add 1 large egg and 1 large egg yolk, one at a time, whisking or mixing after each addition until smooth and shiny batter forms.

Flour & Chocolate: Now add flour mixture all at once and mix with a spatula, or with a mixer just until combined. Then add 1 1/4 cups semisweet chocolate chips and 3/4 cup chopped pecans/walnuts (if using) and mix again to combine.

Portion: Using a 3 tablespoon cookie scoop, scoop up some dough and place 8 balls per baking sheet, spacing them evenly between each other.

Bake the cookies for about 10-14 minutes. You want the cookies to be golden brown with the edges set, but the middle still soft and puffy. Each oven is different, so you will have to figure out for yourself how many minutes exactly (between 10-14) is the perfect chewiness texture for you. I bake mine for 11 minutes.