2 c whole milk
1 c heavy cream
1 pound dulce de leche
1/8 tsp vanilla
Bring milk and cream to a boil. Remove from heat and whisk in dulce de leche. Whisk in vanilla and transfer to a metal bowl. Quick-chill by putting bowl in a larger bowl of ice and water and stirring occassionally until cold, 15-20 minutes.
Freeze mixture in an ice cream maker until almost firm.