In a blender mix the milk, eggs and dulce de leche. Pour the mix into the ramekins. Put the ramekins in a deep dish or tray. Add water to the tray and cover with aluminum foil.
Bake for 50 minutes. If using small ramekins, reduce time to 40 minutes. Remove from oven and allow to cool. Chill in the fridge for 4 hours or overnight. Remove from the ramekins.