Preheat oven to 350°F. Spread oats and pecans in an even layer on a large rimmed baking sheet. Bake 10 minutes or until toasted and fragrant; cool on pan.
Meanwhile, beat butter and sugars on high speed in the bowl of a stand mixer fitted with the paddle attachment (or use hand mixer) until fluffy, about 5 minutes.
Add eggs and egg yolks, one at a time, beating well after each addition. Beat in vanilla.
Combine flour, baking powder, baking soda, and salt in a large bowl. With the mixer running on low speed, gradually beat into butter mixture until blended. Do not overmix.
Stir in oats, pecans, and chocolate chips. Cover dough and chill at least 30 minutes or up to 3 days.
Preheat oven to 350°F. Line 2 baking sheets with parchment paper. Scoop dough using a 2 oz cookie dough scoop 2-inches apart onto prepared baking sheets.
Bake 12 to 15 minutes or until edges are golden brown.