1. Preheat oven to 375º. Bake pecans in a single layer in a shallow pan 8 to 9 minutes or until toasted and fragrant, stirring halfway through. Let cool completely (about 30 minutes).
2. Beat butter at medium speed with an electric mixer until creamy; gradually add sugar and molasses, beating well. Add eggs and vanilla; beat well.
3. Stir together flour and next 4 ingredients. Add to butter mixture; beat at low speed until well blended. Stir in oatmeal, raisins, and pecans. (If desired, store dough in an airtight container in refrigerator up to 1 week.)
4. Drop cookie dough by heaping tablespoonfuls 2 inches apart onto parchment paper-lined or lightly greased baking sheets.
5. Bake at 375º for 9 to 10 minutes or until lightly browned. (Bake chilled dough 10 to 11 minutes.) Cool on baking sheets on a wire rack 5 minutes; transfer to wire racks, and cool completely (about 30 minutes).