Pre-heat oven to 350 degrees and grease a 9″x9″ baking pan.
In a stand mixer (or large mixing bowl with a hand mixer), cream together butter and brown sugar, until fluffy.
Add flour to the mixer and mix gently until it comes together and turns into coarse crumbs.
Press the dough mixture onto bottom of the prepared pan, reserving about ¾ cup of the crumbs to use for the topping. Bake shortbread crust for 9 minutes.
When crust is almost done baking, make filling. In a medium saucepan, heat condensed milk and white chocolate chips over medium heat until melted and smooth.
Take crust out of oven and pour white chocolate mixture over the shortbread.
Mix together the remaining crumbs and crushed candy canes together. Sprinkle mixture on top of the white chocolate layer and bake for another 18-20 minutes, until top is set.
Let cool completely before slicing.