Place an oven rack slightly lower than center in oven and preheat oven to 300 degrees F (150 degrees C).
Whisk milk, cream, 2/3 cup sugar, salt, scrapings from vanilla bean, and split vanilla bean in a saucepan over medium heat until the mixture just reaches a boil; remove from heat and set aside to cool, about 10 minutes.
Whisk egg yolks in a bowl for a few strokes; whisk in hot cream mixture about 1 tablespoon at a time at first, whisking thoroughly before adding the next amount. As the yolk mixture becomes warmer, increase the amount of cream mixture you whisk in to about 1/4 cup at a time.
Strain the cream through a fine sieve and spoon into 8 4-ounce ramekins. Discard spent vanilla pod. Set the ramekins into a roasting pan and pour in enough hot water to reach halfway up the sides of the ramekins.
Bake in the preheated oven until the desserts are softly set, 40 to 45 minutes. Remove the roasting pan and let the desserts cool in the water bath to room temperature. Chill in refrigerator at least 2 hours. Desserts will hold for 2 to 3 days in refrigerator before topping with sugar.
Sprinkle about 1/2 tablespoon of sugar evenly over the top of each dessert. Use a kitchen torch to lightly brown and caramelize the sugar until melted, about 1 minute. Move the torch quickly to avoid burning. Let caramelized topping cool for about 10 minutes, then serve.
