4 Rice Krispies squares, chopped into ice cube-sized cubes
Lightly spray ice cube tray with cooking spray and set aside.
In a double boiler over gentle heat, melt chopped chocolate. When smooth, stir in butter. Spoon 2 tablespoons of chocolate into each tray opening, and tilt tray in all directions, allowing chocolate to cover the sides. Set aside for a couple of minutes to allow a candy shell to form, then refrigerate for 5 minutes.
Fill the tray by piping in 2 teaspoons of salted caramel sauce, then sprinkle with flake salt. Place a Rice Krispies square in each recess. When finished, pour remaining chocolate over the entire tray. Knock the tray on the countertop to remove air bubbles, and refrigerate for 1 hour until set.