Crush cookies in a plastic bag with a potato masher or a metal spoon.
Blend together ice cream, pumpkin, milk, brown sugar, vanilla and spices.
Layer in some of the crushed cookies on the bottom of the glass.
Add a layer of caramel above that and sprinkle with sea salt.
Add in some of you pumpkin pie milkshake to about the halfway point.
Add in another later of cookie, caramel and sea salt.
Fill the glass the rest of the way with the milkshake.
Top with whipped cream. Add on more crush cookie, a drizzle of caramel and a sprinkle of sea salt.
Serve immediately