Step 1

Make the shortbread base: Preheat the oven to 350°F and line a 9x9-inch or 8x8-inch square baking pan with parchment paper, leaving an overhang on two opposite sides for easy removal.

Step 2

In a medium bowl, combine the all-purpose flour, granulated sugar, and salt. Mix well.

Step 3

Add the cold, cubed butter to the dry ingredients. Using a pastry cutter or your fingers, work the butter into the flour mixture until it resembles coarse crumbs.

Step 4

Press the mixture firmly and evenly into the bottom of the prepared pan. Use the back of a spoon or the bottom of a glass and press to ensure it's well-compacted.

Step 5

Bake for about 30-35 minutes or until the edges are lightly golden. Remove from the oven and allow it to cool in the pan while you make the caramel.

Step 6

Make the caramel layer: In a medium-sized saucepan, combine the sweetened condensed milk, butter, light brown sugar, corn syrup (or golden syrup), vanilla extract, and salt.

Step 7

Heat the mixture over medium heat, stirring constantly, until the butter has melted and the sugar has dissolved.

Step 8

Turn heat to low. Continue to cook the mixture, stirring constantly, for 8-10 minutes or until it thickens and turns a rich caramel color (it may come to a slight bubble which is fine). Be careful not to let it burn.

Step 9

Once the caramel is ready, immediately pour it over the cooled shortbread layer, spreading it evenly with a spatula. Allow it to cool and set for about 30 minutes at room temperature or in the refrigerator.

Step 10

Add the chocolate topping: In a microwave-safe bowl, add the chocolate chips, butter, and heavy whipping cream. Microwave in 15-20 second intervals, stirring each time, until smooth (don’t overheat or it will become too thick).

Step 11

Pour the melted chocolate over the caramel layer, spreading it evenly to cover the entire surface. Top the chocolate with sea salt.

Step 12

Allow the chocolate to cool and set. You can speed up this process by placing the pan in the refrigerator for about 30 minutes.

Step 13

Once the chocolate has set, use the parchment paper overhangs to lift the entire slab out of the pan.

Step 14

Place it on a cutting board and use a sharp knife dipped in hot water to slice it into squares or bars.

Step 15

Enjoy your homemade Millionaire's Shortbread!