In a heavy-bottomed pot, melt butter over medium heat. Add brown sugar and keep stirring until the brown sugar and butter are completely melted.

Stir in cornstarch. Add heavy cream and whole milk.

Bring to a slow rolling boil and let thicken. Continue to cook and stir until the mixture coats the back of a spoon.

While the milk mixture is cooking, place egg yolks in small bowl. Temper egg yolks by spooning a small amount of hot milk into the bowl. Use a whisk and keep stirring. Pour the mixture back into the pot.

Bring it back to a boil for 1 minute.

Add vanilla extract or vanilla bean.

Let chill in refrigerator and cool completely. If you want to expedite the cooling process, put in an ice bath.

Two Methods:

In a medium saucepan, heat sugar over medium heat, stirring constantly.

The sugar will begin to form clumps and will turn into an amber color. Keep stirring. Watch carefully as the sugar can easily burn.

Once sugar is completely melted, add the butter. The butter will bubble so be careful.

Stir the butter into the caramel until it is completely melted. Use a whisk to stir the sugar and butter.

Drizzle the heavy cream into mixture and stir.

Let it boil for 1-2 minutes.

Remove from heat and stir in sea salt. Let set up.

Melt butter and sugar in a heavy-bottomed saucepan over medium heat. Let melt and stir with wooden spoon or heat-resistant spatula. Keep stirring and cooking until it turns an amber color. Watch it carefully. Stir in heavy cream and sea salt. Boil for 1 minute and let set up.

To make layered dessert:

Layer butterscotch custard and top with salted caramel.