Preheat oven to 350 degrees
Melt together caramels and heavy cream in a medium saucepan over low heat, stirring occasionally until it reaches a smooth consistency. Set aside
In a medium bowl, mix together flour, oats, brown sugar, baking soda, and salt until combined
Pour the melted butter into the flour mixture and mix until combined
Press half of the mixture into a 9x13 baking pan, setting the other half aside
Bake the crust in a preheated oven for 8 minutes until lightly browned
Remove from oven and sprinkle chocolate chips and walnuts over top
Carefully pour the warm caramel over top creating an even layer
Crumble the remaining mixture over top to create the last layer
Return to the oven and bake for an additional 12-15 minutes until lightly browned