Preheat oven to 325 degrees F
Add milk, sweetened condensed milk, vanilla extract, and salt to a large pot set to medium heat or medium low heat. low. Stir frequently to ensure it does not burn on the bottom or form a film on top.
While milk is heating up, add eggs to a large bowl and whip with a hand mixer until fluffy.
When milk begins to steam, add about 1/4 cup at a time to the egg mixture, stirring constantly.
Once you have added half of the hot milk mixture to the egg mixture, add the rest of the hot milk mixture while stirring.
Pour into desired baking containers (custard cups or a larger baking dish) and set aside
Bring water to a boil.
Place a larger pan with high sides in the preheated oven.
Pour boiling water into pan in oven until it reaches about 1/2 inch high.
Place baking dishes with custard mixture into the pan of water in the oven.
Bake for about 1 hour, or until a knife comes out clean when inserted into the center of the custard.
The bake time will vary slightly depending on the size baking dish used, so make sure to check frequently after 45 minutes if using small custard cups.
Remove custard from oven and allow to cool for 1 hour before serving.
Serve at room temperature or chilled with toppings of choice.
Enjoy!