Preheat the oven to 350 degrees F. Line a baking sheet with parchment paper and set aside.
In a medium bowl, mix the whole wheat pastry flour, oats, kosher salt, cinnamon, nutmeg and baking powder with a fork or spoon until combined.
In a large bowl, mix the sugar, melted butter, eggs and vanilla together vigorously with a wooden spoon until glossy. Stir in the dry ingredients just until incorporated. Add the trail mix, chocolate chips, popcorn and coconut and mix to combine.
Drop the cookie dough in heaping tablespoons onto the cookie sheet about 2 inches apart. Bake for 13-15 minutes or until lightly browned. Transfer to a wire rack to cool. Store in an airtight container or refrigerator up to 3 days.