Preheat oven to 350 and line cookie sheets with parchment paper. The parchment paper works better as the cookies seem to bake more evenly, but if necessary, you can use non-stick spray on the pans instead.
If the dried cherries are large, cut them in half.
In a medium bowl, whisk together the flour, salt, baking soda and baking powder; set aside.
Using an electric mixer on high speed, cream the butter, granulated sugar and brown sugar together until light and fluffy, about 2 minutes. Add the eggs and vanilla and beat until well-mixed, about 15-30 seconds.
Add in the flour mixture, and beat at low speed until combined.
At low speed, mix in the oats.
Add the dried cherries and white chocolate (and walnuts, if using) at low speed, until just combined and mixed through.
Drop by tablespoonfuls onto the prepared cookie sheets about 2 1/2 inches apart.
Bake for about 10-12 minutes, until very lightly browned. You don't want these too dark or overcooked so they come out a bit chewy.
Leave on the sheet for a minute to give the cookies a chance to set, then remove to a rack to cool completely.
You can make them smaller, or, as in the original recipe, drop by 2 oz. cookie scoops to make large cookies. Adjust the baking time accordingly. (About 8-10 minutes for smaller, 20 minutes for large.).