Preheat your oven to 350°F (177°C) and lightly grease an 8×8-inch baking dish.
In a large bowl, beat together the eggs, sugar, vanilla, and salt until smooth and well combined.
In a small saucepan, heat the milk to about 180°F (just before it begins to simmer, but do not let it boil).
Slowly pour the hot milk into the egg mixture in a thin stream, whisking constantly to avoid curdling. Continue whisking for another minute once combined.
Pour the custard mixture into the prepared baking dish. Sprinkle a pinch of nutmeg on top, if desired.
Place the baking dish into a larger dish filled with about 1 inch of water to create a water bath.
Carefully place both dishes in the preheated oven and bake for 45-50 minutes, or until a knife inserted into the center of the custard comes out clean. The custard should still have a slight jiggle.
Remove from the oven and let cool. Serve warm or chilled, topped with whipped cream, fruit, or additional spices if desired. Refrigerate any leftovers.