In a large mixing bowl, combine the butter, sugars, salt, and vanilla on low speed until light and fluffy.
Add the eggs one at a time, mixing well after each addition.
In a large bowl, combine the flour, baking soda, baking powder, and cinnamon.
Add the flour mixture to the mixing bowl, and beat on low until just combined.
Fold in the oats, coconut, carrots, and walnuts.
Chill dough for at least 30 minutes.
Drop by tablespoonfuls onto parchment paper-lined baking sheets, about 2 inches apart.
Bake at 350 degrees for 12 to 14 minutes, or until the tops feel set when you tap them with your finger. Edges will be golden brown.
Allow the cookies to cool for 1-2 minutes on the baking sheets before removing to a wire rack to cool completely.
Once completely cooled, assemble the whoopie pies.