Preheat oven to 350°F and line baking sheet(s) with parchment paper.
In a medium bowl, whisk together the flour, baking soda, baking powder, cinnamon, nutmeg, ginger and salt.
In a large bowl, cream together the butter and sugars really well. Add the eggs and vanilla one at a time and mix until light and fluffy.
Gradually mix the dry ingredients into the wet ingredients, just until combined. Scrape the sides and bottom of the bowl as necessary.
Gently stir in the chocolate chips, oats, coconut and walnuts (again, just until combined).
Split the dough into 4 even balls and place them on baking sheets, leaving at least 3 inches between each ball (I bake 2 cookies per sheet). Press down on the dough to flatten them slightly (~½ inch height, 4-5 inches in diameter).
Bake until the edges are slightly tan (about 13-17 minutes). The centers may not look fully done but that's okay, they'll continue baking from the heat of the pan.The baked cookies should be ~6-7 inches in diameter.If they aren't perfectly round, immediately run a flat edge around the side to form nice circles.
Let them cool on the pan until they're firm enough to transfer to a cooling rack, then let them finish cooling completely.