Preheat the oven to 350 degrees and line 2 sheet trays with parchment paper or use a split.
In a small bowl, combine flour, oats, cinnamon, baking soda, salt and cornstarch. Set aside.
In a large bowl, cream together the butter, brown sugar, white sugar, egg and molasses. Stir until completely smooth. Add in the dry mixture and stir until evenly mixed.
Add in the cherries or raisins, walnuts and chocolate chips and mix in.
Let Cool on rack and store in an airtight container.
FOR LARGE COOKIES: If making large cookies, portion cookie dough into 1/3 cup balls and roll in between palms to make round. It will make exactly 8 cookies. Press balls down with the palm of your hand to flatten slightly.
Cook 4 on a tray, but only 1 tray at a time. Space evenly and bake for 13 to 15 minutes or until cookies are light golden brown.
FOR SMALLER COOKIES: Use a medium cookie scoop to for normal size cookies. You will get approximately 15 to 18 cookies. Make sure you press balls down slightly with palm of hand before baking. The cornstarch in the cookies makes them stay quite puffy!
Baking time will be 10 to 12 minutes or until lightly golden brown.