Preheat the oven to 160 degrees C. Lightly grease a 4-cup heatproof dish or 4 ramekins.
Heat the milk and cream in a small saucepan over medium heat until hot. Do not boil.
Whisk the eggs, caster sugar and vanilla in a large bowl until combined. Gradually pour the warm milk mixture into the eggs, whisking constantly. Strain the mixture through a sieve into the prepared baking dish and sprinkle with grated nutmeg.
Place the dish in a large roasting pan. Pour enough warm water into the roasting pan to reach two-thirds of the way up the side of the dish. Bake for 1 hour, or until the surface is firm when touched lightly (if you're baking individual custards, start checking after about 35 minutes).
Carefully remove the custard from the oven and stand at room temperature to cool. Spoon into serving bowls and serve with seasonal fruit.