Grease a 13”x9” baking dish with cooking spray. Line the pan with parchment paper that overhangs on all four sides of the pan.

In a large pot, stir together butter, sugar, brown sugar, corn syrup, evaporated milk, cream and salt. Set pot over medium heat and stir until the butter is melted and ingredients are mixed. Wash down the sides of the pot with a wet pastry brush to remove any uncooked sugar crystals. Clip a candy thermometer to the side of the pot; do not allow tip to touch the bottom.

Bring to mixture to a boil over medium heat and continue to cook, without stirring, until temperature reads 248°-250°F. Remove from heat and stir in the with a clean metal or heat resistant spoon.

Carefully pour mixture into the prepared dish and allow to cool 15 minutes, then refrigerate until firm, about 1-½ hours. Lift the caramel out of the pan and cut into rectangles or squares of desired size. If desired, drizzle with white and milk chocolate candy wafers and sprinkle with crushed toffee bits before chocolate sets. Wrap pieces individually in squares of twisting waxed paper.