Regulate racks to upper- and lower- center positions and preheat the oven to 350° F. Line two cookie sheets with parchment paper and put aside.
In a medium bowl, whisk collectively the bottom oats, flour, baking powder, baking soda and salt.
Within the bowl of an electrical mixer, beat the butter and sugars at medium pace till gentle and fluffy, about Three minutes. Scrape down the perimeters of the bowl with a rubber spatula. Add the egg and vanilla; proceed beating till mixed. Scrape down sides of bowl. Add the dry components and beat at low pace till simply mixed. Add the chocolate chips, coconut and nuts and blend till evenly mixed.
Working with 1-1/2 tablespoons of cookie dough at a time, kind balls and place on parchment-lined cookie sheets, leaving at the least 2 inches between them. (Hold remaining batter cool in fridge whereas first batch cooks.) Bake, reversing place of cookie sheets midway via baking, till edges of cookies start to crisp however facilities are nonetheless comfortable, 12 to 14 minutes. Cool cookies on baking sheets for 1 minute, then switch to racks to chill utterly. Repeat with remaining batter.