Step 1

In a large bowl, whisk together the yolks, salt and vanilla. Set aside while you make the butterscotch.

Step 2

Melt the butter over medium low heat. Add the brown sugar and stir until the sugar looks like wet sand.

Step 3

Cook on medium low, stirring occasionally, for 5 minutes. The mixture will begin to liquify.

Step 4

Slowly whisk in 1 cup of the cream. BE CAREFUL, the mixture will bubble up and steam when the liquids are added. Keep your face away from the pot.

Step 5

Cook over low heat for 10 minutes, whisking occasionally until the butterscotch becomes more viscous, very smooth and silky. Whisk in the remaining cream and the milk. Reduce the heat to low.

Step 6

Whisk a cup of the hot butterscotch into the yolks. Pour the mixture back into the pan. Stirring constantly, cook the custard until it thickens enough to coat the back of a spatula or wooden spoon. Remove from the heat and strain into the bowl. Stir in the bourbon. Cover the bowl and chill until very cold. At least 4-5 hours or over night.

Step 7

Churn the ice cream according to the directions for your ice cream machine. Scoop the ice cream into a freezer container. Smooth the top and lay a piece of plastic wrap directly on the surface of the ice cream. Cover tightly and freeze until firm.