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

In a mixing bowl, whisk together the flour, oatmeal, baking soda, salt, and brown sugar and blend well.

In a separate bowl, cream the butter, eggs, and peanut butter with an electric mixer on medium speed until light and fluffy.

Gradually add the dry ingredients to the wet ingredients, mixing with mixer until combined.

Fold in the toasted pecans (chopped pecans or unchopped) until evenly distributed throughout the dough.

Cover the cookie dough with plastic wrap. Place the wrapped cookie dough in the refrigerator and let it chill for about one hour.

Remove the dough from the refrigerator. Use a cookie scoop or a spoon to portion it into evenly sized-balls. Use a fork to gently flatten each dough ball into a cookie shape or your desired thickness. Place them on the lined baking sheets, leaving some space between each cookie.

Bake in the preheated oven for 11-12 minutes or until the cookies are golden brown around the edges.

Allow the cookies to cool on the cookie sheet for a few minutes before transferring them to a wire rack to cool completely. Enjoy!