Step 1

Preheat oven to 350F. Spray a 9x13 inch baking dish with nonstick spray.

Step 2

Prepare cake mix according to package directions, using milk instead of water. Pour batter into prepared dish and bake according to directions on box. Let cake cool completely.

Step 3

Use the end of a wooden spoon to poke holes all over cake. Pour sweetened condensed milk over the cake, making sure to fill the holes. Drizzle cake with half of salted caramel sauce.

Step 4

Whip heavy whipping cream on medium high speed with an electric mixer. With mixer running, add powdered sugar and vanilla extract. Whip until stiff peaks form.

Step 5

Spread whipped cream over the cake. Drizzle with remaining caramel sauce and sprinkle with Heath candy pieces.