Spray bottom of slow cooker with nonstick spray, coating it well.
With a mixer, beat together butter, sugar, and vanilla.
Add egg and regular salt and mix until combined.
Add flour 1 cup at a time and continue mixing until soft dough forms.
Sprinkle a bit of flour over dough and use your hands to form into a ball.
Use a little over half of the dough and press down evenly on bottom of slow cooker. Use a sprinkle of flour as needed to keep dough from sticking to your hands.
Sprinkle bag of caramel bits evenly over crust.
Crumble remaining dough over top of caramel layer.
Top it off by sprinkling sea salt across crumbled dough layer.
Cover and cook for 2 - 3 hours on low. (Cookie bars are done when they are slightly browned around the edges and a knife inserted into center of the bars is mostly clean.)