Preheat oven to 375°F (190°C). Rinse frozen cranberries under cold water until separated. Toss in a bowl with 1/3 cup sugar and set aside.
In a large bowl, cream shortening/butter, brown sugar, and 1 cup granulated sugar together until fluffy.
Beat in eggs, milk, and vanilla extract until well combined.
Gradually stir in flour, salt, and baking soda, scraping the sides of the bowl.
Alternately fold in quick oats, white chocolate chips, and sugar-coated cranberries until a thick dough forms.
Drop rounded tablespoonfuls 2 inches apart on ungreased baking sheets. Bake for exactly 9 minutes until bottoms are light golden.
Rest on the baking sheet for 3 minutes before transferring to a wire rack to cool completely.