Step 1

Adjust oven rack to middle position and heat oven to 350 degrees. Line 2 rimless cookie sheets with parchment paper. Whisk flour, baking powder, baking soda, and salt together in bowl.

Step 2

Whisk sugar, melted butter, egg and yolk, and vanilla in large bowl until combined. Stir in flour mixture until no dry streaks remain. Stir in oats, pecans, coconut, and chocolate chips until fully combined (mixture will be sticky).

Step 3

Lightly spray 1/4-cup dry measuring cup with vegetable oil spray. Drop level 1/4-cup portions of dough onto prepared sheets, staggering 8 portions per sheet and spacing them about 2 1/2 inches apart. Divide any remaining dough among portions.

Step 4

Bake cookies, 1 sheet at a time, until edges are browned and set and centers are puffed with pale, raw spots, 15 to 17 minutes, rotating sheet halfway through baking. Do not overbake.

Step 5

Let cookies cool on sheet for 5 minutes, then transfer to wire rack and let cool completely before serving. (Cookies can be stored in airtight container for up to 3 days.)

Step 6

TO MAKE AHEAD: At end of step 3, wrap sheets tightly in plastic wrap and refrigerate for up to 2 days. When ready to bake, increase baking time to 16 to 18 minutes. To freeze, portion dough onto parchment-lined sheet and freeze until solid. Transfer frozen portions to zipper-lock bag and freeze for up to 2 months. Do not thaw before baking. Increase baking time to 17 to 19 minutes.