Preheat oven to 350 degrees F.
Line a 9 x 13-inch baking pan with foil, leaving an overhang, or extra foil along the sides to help lift the bars from the pan after baking. Butter the bottom and sides of the foil lined pan. Set aside.
Spread old fashioned rolled oats in single layer on large baking sheet. Toast in preheated oven for 10 to 12 minutes, stirring once after about 5 minutes. Oats should be lightly golden.
Remove toasted oats from oven and cool completely.
Add toasted oats, chopped pecans, fine sea salt, and all-purpose flour to medium mixing bowl. Whisk to combine. Set aside.
Add unsalted butter and brown sugar to stand mixer. Beat on medium until smooth. About 4 minutes. Add eggs, vanilla bean paste, and heavy cream to stand mixer bowl. Beat about 1 minute or until well incorporated.
Remove bowl from stand mixer. Add toasted oats mix to stand mixer bowl. Stir well with a wooden spoon or your hands.
Spread about 2/3 of the toasted oats mixture evenly onto the bottom of the baking pan.
Add dark chocolate chunks and sweetened condensed milk to small saucepan. Heat over low heat, stirring occasionally, until the chocolate has melted and the mixture is well combined and smooth.
Pour the chocolate mixture over the oat pecan base. Spread evenly with an offset spatula.
Add soft caramel candies and heavy cream to small saucepan. Heat over low heat, stirring constantly, until the caramels have melted and the mixture is well combined and smooth.
Pour melted caramel over chocolate layer. Spread evenly with an offset spatula.
Dollop toasted oats mixture over caramel, leaving gaps. Place pecan halves, ridges facing up, randomly across the top of the caramel and oats.
Bake 30 minutes in preheated oven. Remove from oven and cool completely on wire rack. Remove bars from pan using foil overhang. Remove foil and cut bars into desired shapes.