Toast the Pecans: In a skillet over medium heat, toast the pecans for a few minutes, stirring occasionally until golden and aromatic. Remove from heat, let cool, and then chop finely with a knife or in a food processor.
Cream Butter and Sugars: In a large bowl, beat the room-temperature butter, brown sugar, granulated sugar and vanilla extract until light and creamy, about 2-3 minutes.
Add Eggs: Add the eggs, beating well for about 1 minute until fully combined.
Add Dry Ingredients and Pecans: Sift in the flour,finely chopped nuts, baking soda, and salt, and mix just until combined.
Chill the Dough: Cover the dough and refrigerate for at least 3 hours, or overnight if possible. This resting time is essential for better texture and flavor.
Form and Decorate the Cookies: Using a #20 cookie scoop (about 3 tablespoons of dough per cookie), form dough balls. Place a whole pecan on top of each ball for decoration.
Bake: Preheat the oven to 350°F (175°C). Place the dough balls on a parchment-lined baking sheet, leaving space between each one. Bake for about 15 minutes, or until the edges are golden.
Cool and Serve: Let the cookies cool on the baking sheet for a few minutes before transferring them to a wire rack to cool completely.