Classic Vanilla Ice Cream

In heavy saucepan stir together cream, milk, half the sugar, and the salt. With a small knife split the vanilla bean lengthwise and scrape seeds from bean. Add seeds and split bean to pan. Heat over medium-high heat. When mixture just begins to bubble around edges, remove from heat; cover. Let seeds and split bean soak for 30 minutes to infuse the liquid. Remove and discard vanilla bean.

Place egg yolks in a medium heatproof bowl and whisk just enough to break up yolks. Whisk in remaining sugar until smooth. (The sugar dilutes the eggs a bit and prevents them from scrambling when the hot cream is added.) Set aside. Uncover cream mixture and heat over medium-high heat until almost simmering. Reduce heat to medium.

Using a ladle, carefully scoop out about 1/2 cup of the hot cream; whisking constantly, pour into yolks. Repeat. (This step, known as tempering, gradually heats the yolks to reduce the risk of overcooking.) Stirring constantly with a wooden spoon, slowly pour yolk mixture into hot cream in saucepan. Continue to cook on medium, stirring constantly in a figure eight to cover entire bottom of pan. Pay close attention as the consistency can change quickly. Cook until mixture goes from the consistency of heavy cream to that of a thin puree, but no thicker. You'll notice the mixture thickening slightly and feel a little more resistance as you stir.

To test the readiness of the custard, remove the spoon from the saucepan and drag your finger across it. If the base coats the back of the spoon and the path made by your finger holds for a second or two, it's ready. Remove the pan from heat and immediately pour through a fine-mesh sieve into a measuring cup or small bowl.

Set the bowl in a larger bowl of ice water and stir frequently with a clean spatula until cool. Remove and cover with plastic wrap. Refrigerate for at least two hours until completely cold. Stir in vanilla extract just before churning and freezing the ice cream.