Preheat oven to 350°. Place pecans on a rimmed baking sheet. Line several other rimmed baking sheets with parchment paper.
Bake pecans until lightly toasted, 8 to 10 minutes. Remove from oven and let cool before chopping.
In large mixing bowl, beat together butter and both sugars with a mixer at medium-high speed until light and fluffy. Add egg and vanilla, beating until blended.
In a large bowl, whisk together oats, flour, baking soda, cinnamon, and salt. Add to butter-sugar mixture, 1 cup at a time, until dough is well blended. Stir in cherries, chocolate chips, and chopped pecans. (Dough will be thick). Drop ¼-cup portions of dough 3 inches apart on prepared baking sheets.
Bake until cookies are golden brown, 13 to 15 minutes. Remove from oven and let cool on baking sheets for a few minutes before serving.
Notes
*Can be made with white chocolate chips or dark chocolate chips as well.
Recipe by TeaTime Magazine at https://teatimemagazine.com/darci-hannah-takes-reader-mystery-ride-murder-beacon-bakeshop/