1. In double boiler over hot, not boiling, water, combine egg yolks, milk, salt, and 3/4 cup sugar. Cook, stirring constantly, until mixture thickens and coats a spoon, about 15 minutes. Stir in vanilla; pour into four 16-ounce wine goblets or dessert bowls; cover and refrigerate until well chilled, about 1 hour.
2. Meanwhile, in small bowl, with mixer at high speed, beat egg white until soft peaks form; sprinkle in 2 tablespoons sugar, beating until sugar completely dissolves and white stands in stiff, glossy peaks.
3. Preheat oven to 350°F. Onto 1/2 inch cold water in 8" by 8" baking dish, drop egg white (meringue) by 1/3 cups, making 4 mounds. Bake 7 to 10 minutes, until lightly browned.
4. With slotted spoon, carefully remove each meringue from water; drain (still held on spoon) on paper towels. Carefully slip a meringue onto custard in each goblet.
5. In heavy 1-quart saucepan over high heat, heat 3 tablespoons sugar, stirring constantly, until smooth and amber-colored, about 3 minutes. Remove from heat; let stand 2 minutes. With spoon, quickly drizzle caramelized sugar over each dessert in thin strands.