Cream the softened unsalted butter, granulated sugar, and packed brown sugar in a large mixing bowl using an electric mixer until light and fluffy (about 2-3 minutes).
Add the eggs one at a time, mixing well after each addition. Stir in the vanilla extract until combined.
In another bowl, whisk together the all-purpose flour, baking soda, baking powder, and kosher salt. Gradually add this dry mixture to the wet ingredients, mixing on low speed until just combined.
Gently fold in the semi-sweet chocolate chips and chopped pecans until evenly distributed throughout the dough.
In a small bowl, mix together the packed brown sugar, softened unsalted butter, and ground cinnamon until a thick paste forms.
Scoop out half of the cookie dough onto a piece of parchment paper. Spread the cinnamon mixture evenly over the dough. Use the other half of the dough to cover the cinnamon layer. Gently swirl the two doughs together with a knife, being careful not to mix completely.
Wrap the dough in the parchment paper and refrigerate for at least 30 minutes.
Preheat your oven to 350°F (175°C) and line your baking sheets with parchment paper. Use a cookie scoop to drop rounded tablespoons of dough onto the prepared sheets, leaving space between each cookie.
Bake in the preheated oven for 10-12 minutes, or until the edges are lightly golden.
Allow the cookies to cool on the baking sheets for 5 minutes before transferring them to a wire rack to cool completely.
