Prepare the crust: Preheat oven to 350°F (175°C). Mix graham cracker crumbs, melted butter, and sugar. Press into a greased 9x13-inch pan. Bake 8-10 minutes until lightly golden. Cool.
Make the pumpkin filling: Whisk pumpkin puree, brown sugar, eggs, vanilla, cinnamon, nutmeg, ginger, salt, and heavy cream until smooth. Pour over cooled crust and bake 25-30 minutes until set. Cool completely.
Prepare the salted caramel: Melt butter in a small saucepan over medium heat. Stir in brown sugar and heavy cream, cooking 3-4 minutes until smooth. Remove from heat and stir in vanilla and sea salt. Cool slightly. Drizzle over cooled bars.
Chill and serve: Refrigerate for at least 2 hours until caramel sets. Cut into squares and enjoy!