Preheat the oven to 325°F (165°C).
In a mixing bowl, whisk together the eggs, sugar, vanilla extract, and salt until well combined.
Gently heat the milk in a saucepan until it's warm but not boiling. Gradually whisk the milk into the egg mixture.
Pour the mixture into individual ramekins.
Place the ramekins in a baking dish and fill the dish with hot water until it reaches halfway up the sides of the ramekins.
Bake in the preheated oven for 30-40 minutes, or until the custard is set and a knife inserted in the center comes out clean.
Remove from the oven and allow to cool. Serve warm or chilled.