In a medium bowl, whisk together the flour, cinnamon, baking soda, and salt. Set aside.

In a large mixing bowl or the bowl of a stand mixer fitted with the paddle attachment, combine the butter and both sugars. Beat on medium speed until light and fluffy, about 3 minutes.

Reduce the speed to low. Add the vanilla and egg, and beat until well mixed, about 1 minute. Stop and scrape down the bowl. Add flour mixture, and mix until the flour is mostly incorporated, then scrape the bowl down again.

Add the oats, chocolate chips, coconut, and pecans, and mix on low speed until the flour is fully combined and the mix-ins are well distributed throughout the dough. Cover and refrigerate the dough for 1 hour or up to 24 hours. (If chilling for more than 1 hour, you may need to let the dough sit on the counter for 15 to 20 minutes to soften slightly for easier scooping.)

Preheat the oven to 375°F. Line two baking sheets with parchment paper.

Using a 2 tablespoon-scoop, scoop the dough into balls and place about 2 inches apart on the baking sheets.

Bake one sheet at a time for 8 to 10 minutes, or until the cookies are golden around the edges but still soft in the center. Let the cookies cool on baking sheets for a few minutes, then transfer to a wire rack, and let cool completely.