Preheat oven to 325°F. Bring milk to simmer in heavy medium saucepan. Remove from heat; keep warm. Combine 1-2/3 cups sugar and 1/3 cup water in heavy medium saucepan. Stir over medium heat until sugar dissolves. Increase heat to high and boil without stirring until deep golden brown, brushing down sides of pan with wet pastry brush if sugar crystals form and swirling pan occasionally, about 10 minutes. Carefully measure 1/2 cup hot caramel in heatproof measuring cup and pour into hot milk (mixture will bubble vigorously). Immediately pour remaining caramel into eight 3/4-cup custard cups, dividing evenly. Stir milk and caramel mixture over medium heat to melt any undissolved caramel. Whisk egg yolks, eggs, vanilla, salt and remaining 1/3 cup sugar in large bowl. Gradually whisk in hot milk mixture. Strain into large pitcher. Divide mixture among prepared custard cups. Place custard cups in large roasting pan. Place pan in oven. Pour enough hot water into roasting pan to come halfway up sides of cups. Bake until centers are set, about 55 minutes. Carefully remove pan from oven. Using tongs, remove custard cups from water. Cool 30 minutes. Cover and chill at least 6 hours or overnight. Using small sharp knife, loosen sides of custards. Place plate over each custard, invert onto plate and serve.