- Preheat the oven to 325°F.
- Cook the sugar in a small heavy saucepan over low heat, without the water, swirling the pan constantly, until brown.
- Stir the hot water into the caramel, being careful to guard against splattering (the mixture will bubble vigorously).
- Boil the mixture, swirling the pan occasionally, until the sugar is thoroughly dissolved, about 2 minutes.
- Pour the caramel syrup into a 1-quart souffle dish or five 4-ounce ramekins.
- Tilt the molds to coat all of the surfaces with caramel.
- Combine the coconut milk, milk and sugar in a medium saucepan over low heat.
- Scald until the sugar dissolves completely.
- Remove from heat.
- In a large bowl, whisk the eggs and vanilla.
- Gradually whisk the hot coconut milk mixture into the eggs, blending thoroughly.
- Strain the custard through a fine sieve into a bowl.
- Carefully pour into the caramel-lined souffle dish or ramekins.
- Line a large roasting pan with 2 layers of paper towels (see note).
- Put the soufflé dish or ramekins in the roasting pan and add hot water to reach halfway up the side of the dish.
- Bake in the center of the oven for 50 minutes (30 minutes if using ramekins), or until a knife inserted in the center comes out clean.
- Be careful not to let the water boil; do not disturb the custard while baking.
- This is the only "secret" to producing a smooth and velvety custard.
- Remove the souffle dish or ramekins immediately from the hot water.
- Allow to cool in a cold-water bath.
- Chill thoroughly.
- To serve, run a knife around the edge of the custard and turn out onto dessert plates.
- Serve with shaved ice or whipped cream, if desired.