Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper.

In a mixing bowl, cream together the softened unsalted butter, granulated sugar, and dark brown sugar for about 2-3 minutes using an electric mixer until light and fluffy.

Add the large egg and vanilla extract, beating on low speed until fully combined and smooth.

In a separate bowl, whisk together the all-purpose flour, baking soda, baking powder, and kosher salt. Gradually incorporate this into the wet ingredients.

Gently fold in the chopped dark chocolate and chopped pecans with a spatula.

Cover the bowl with plastic wrap and chill the dough in the refrigerator for 20-30 minutes.

Scoop the chilled dough onto the prepared baking sheet, spacing each dollop about 2 inches apart. Optionally sprinkle flaky sea salt on top.

Bake for 10-12 minutes until the edges are golden brown, keeping the centers soft.

Remove from the oven and let them cool on the baking sheet for about 5 minutes before transferring to a wire rack to cool completely.