In a heavy bottom pot simmer heavy cream, milk, sugar and salt until the sugar completely dissolves and remove pot from heat.

In a separate bowl, whisk yolks well.

Continue whisking constantly and slowly whisk about a third of the hot cream into the yolks, then whisk the yolk mixture back into the pot with the cream.

Return pot to medium-low heat and gently cook until mixture is thick enough to coat the back of a spoon.

Remove from heat and strain through a fine-mesh sieve into a bowl. Allow mixture to cool to room temperature. Lay plastic wrap directly over custard mixture and chill at least 4 hours or overnight.

Cream peanut butter and the butter. Add sugar and continue to cream until well blended. Blend in vanilla and salt.

In a separate bowl combine flour, baking powder and baking soda with a whisk, and add to creamed mixture. Mix until just combined. Set aside

Add the well chilled custard base to the ice cream maker and allow to churn for 10 to 12 minutes.

Drop small chunks of cookie dough into the base while still churning, allowing each chunk to get pulled in before adding the next.

Churn for an additional minute before pouring in the caramel sauce in a slow stead stream.

Turn off ice cream maker and transfer mixture to a loaf pan.

Freeze until firm.