Frozen Samoa Pie

shortbread cookie crumbs (I used a 5.3 ounce package of Walkers Shortbread Rounds)

granulated sugar

unsalted butter, melted

all-purpose flour

old fashioned oats

packed light brown sugar

, chopped

sweetened shredded coconut

unsalted butter, melted

miniature chocolate chips

cream cheese, room temperature

can sweetened condensed milk

container frozen whipped topping, thawed

pure vanilla extract

, divided use