Beat butter and sugars at medium speed with an electric mixer until creamy. Add eggs and vanilla, beating until blended.
Pulse oats in a food processor to a fine powder. Combine oats, flour, and next 3 ingredients in a large bowl; gradually add to butter mixture, beating well. Stir in chocolate chunks, grated chocolate bars, and pecans. Drop dough by 1/4 cupfuls onto lightly greased baking sheets.
Bake at 375° for 10 to 14 minutes or until desired degree of doneness. Remove cookies to wire racks to cool completely.
Note: For testing purposes only, we used Hershey's milk chocolate candy bars.