In a saucepan, melt the sugar but do not let it burn. It should turn a deep brown. You will need to stir constantly, and may need to remove the pan from the heat occasionally to keep it from burning.
Once the sugar is melted, add the cream and salt and continue heating on low until all the sugar is dissolved into the cream. Make sure the cream doesn't boil.
Put the egg yolks in a mixing bowl and SLOWLY pour in the cream, mixing with a fork. Try not to whip any air into the mixture. Also, be sure to pour slowly or you will end up cooking the egg in the hot cream.
Pour evenly into 3 ramekins and place in a water bath (use a lasagna pan filled partway with water). You want the water bath to come about halfway up the ramekins.
Bake at 350 for anywhere from 30 to 60 minutes. The time will depend on the shape of the ramekins (wide ramekins cook more quickly than narrow ones). Custard is done when it is set but still jiggly in the center. Check after 30 minutes, and then every 5-10 minutes until done.
Remove ramekins from water bath and allow to cool to room temperature, uncovered. Then cover with plastic wrap and chill in the fridge at least 4 hours, and up to 2 days.
When ready to serve, remove from the fridge and top with a couple teaspoons of sugar. Caramelize with a blowtorch or place under the broiler for a minute or two. If using the broiler method, keep a constant watch on them to avoid burning the sugar.