Line a 9 x 9-inch pan with foil and spray the foil with nonstick cooking spray; set pan aside.

In a large saucepan, combine 1 cup Karo® Syrup, 1/3 cup granulated sugar, and 1/3 cup packed light brown sugar. Cook over medium heat, stirring until the sugars dissolve and the mixture comes to a low boil, then immediately remove the pan from the heat.

Stir 1 cup salted caramel chocolate hazelnut spread into the hot syrup mixture until fully combined and smooth.

Add 6 cups crispy rice cereal (plain or cocoa flavored) to the saucepan and stir gently but thoroughly until all the cereal is evenly coated.

Pour the coated cereal into the prepared pan and press it evenly into an even layer using a spatula or lightly greased hands. Set aside.

In a medium saucepan over low heat, combine 1/2 cup salted butter, 1/2 cup packed light brown sugar, 2 tablespoons Karo® Syrup, and 1/2 cup sweetened condensed milk. Stir until the butter melts and the mixture is uniform.

Increase heat as needed to bring the mixture to a boil, stirring constantly. Once boiling, maintain a low boil and continue stirring constantly for about 5 minutes.

Immediately pour the hot caramel evenly over the cereal layer in the pan and spread to cover. Let the bars sit until the caramel begins to set (it will thicken and stop running).

In a small saucepan over low heat, melt 2 cups semisweet chocolate chips, stirring constantly until smooth (watch closely to prevent scorching).

Spread the melted chocolate evenly over the caramel layer.

Cool the pan at least 45 minutes, or until the bars are firm. Use the foil to lift the slab from the pan and cut into bars.