Melt butter in a large skillet over medium heat. Add the chopped pecans and cook, stirring occasionally, for 4 to 5 minutes or until lightly toasted. Set aside to cool until needed.

In a large bowl, whisk together the flour, cornstarch, salt, cinnamon, and baking soda. Set aside.

In a small saucepan over medium heat, melt the butter. Continue to cook the butter, swirling the pan occasionally. Pay close attention: the butter should foam at the top, and you will hear tiny popping noises. As it cooks, the butter will turn a rich amber color, with small brown bits forming at the bottom and a slightly nutty aroma. Once this stage is reached, remove from heat and pour the butter into a large mixing bowl.

Add both sugars to the mixing bowl and whisk well to combine. Add the vanilla extract and mix it in. Beat in the eggs and egg yolk one at a time, making sure each is fully incorporated before adding the next.

Using a rubber spatula, gently fold in the flour mixture, stirring just until combined. Then, fold in the buttered pecans.

Cover the bowl and refrigerate the dough for 4 hours.

Preheat the oven to 375°F (190°C). Line two large baking sheets with parchment paper.

Using a large cookie scoop, divide the dough into 3-tablespoon sized balls and place them onto the prepared baking sheets, spacing them about 3 inches apart to allow for spreading. Press a pecan half gently into the top of each dough ball.

Bake one tray at a time in the preheated oven for 10 to 11 minutes. If the edges spread too much while baking, gently press them back in with a spatula as soon as you remove the cookies from the oven.

Sprinkle the warm cookies with granulated sugar and let them cool on the baking sheet for 15 minutes before carefully transferring them to a cooling rack.