Place 1 stick of butter in a small saucepan and set over medium heat. Heat the butter until it melts, then bubbles, and eventually begins to smell nutty. Whisk and swirl every few seconds until you start to see browned bits (or flecks) at the bottom. Remove immediately.

In a large mixing bowl or the bowl of a stand mixer, add the remaining stick of butter. Pour the hot browned butter over the top. Add the sugars and beat for 2–3 minutes until light and smooth. With the mixing speed on low, add the eggs one at a time until incorporated, then add the vanilla.

In a medium-sized mixing bowl, whisk together the flour, baking soda, and salt. With the mixing speed on low, gradually add in the dry ingredients. Beat until just combined or until a soft dough forms. Fold in the chocolate chips and pecans with a spatula. Cover with plastic wrap and chill for 1 hour.

Preheat the oven to 350 degrees Fahrenheit (177 degrees Celsius). Line baking sheets with parchment paper or baking mats.

To bake the cookies, use a standard-size cookie scoop (approximately 1.5 tbsp.) to form balls of dough. Place the cookie dough balls onto the prepared sheets, leaving at least 2 inches between them. Sprinkle with sea salt if desired.

Place in the oven and bake for 10–12 minutes, rotating the sheet halfway through the baking process. Remove from the oven when the cookies are golden brown in color around the edges. Let the cookies cool on the pan for 3–4 minutes, then transfer to a wire rack to cool completely.