Preheat oven to 350 F. Lightly grease 2 large baking sheets.
In a large mixing bowl, use a handmixer or strong fork to cream together oil and sugars. Mix in the vanilla. Add the cornstarch and milk, and mix until the cornstarch is dissolved.
Sift in the flour, baking soda, spices and salt and mix to combine. Add the oats, cranberries and nuts, and use your hands to form a stiff dough.
Scoop cookies out with a tablespoon or server, using about two tablespoons of dough per cookie. Place about 2 inches apart. Flatten a little with your hand. Bake for 10 to 12 minutes, until edges are lightly browned.
Remove from oven and cool for about 5 minutes then transfer to cooling rack to cool completely.