2/3 cup granulated sugar
2 1/2 cups half-and-half
5 large egg yolks (at room temperature)
Grated zest of 1 large lemon
1/2 cup fresh lemon juice

Combine sugar and half-and-half in a large saucepan and cook over low heat until sugar dissolves, stirring constantly. Set aside.

Beat egg yolks until creamy, then add 1/2 cup of the cream to warm them. Return cream mixture to medium-low heat and stir in the warmed yolks. Cook until the mixture coats the back of a spoon, about 5 minutes.

Remove from heat; stir in the zest and lemon juice. Mix well and allow to cool. Chill.

Pour mixture into an ice cream maker and freeze according to manufacturer's directions.

Makes about 1 1/2 pints.