In heavy-bottomed saucepan, whisk together eggs, yolks, sugar, and lemon juice. Stir in butter. Cook over medium-low heat, stirring constantly with a heat-proof rubber spatula, until mixture is thick enough to coat back of a spoon, about 10 minutes. (Do not allow mixture to come to a boil or it will curdle). Whisk in half-and-half; continue to stir over medium-low heat until thick, 3 to 5 minutes. Strain custard into bowl. Stir in zest.
Cool lemon custard 15 minutes. Pour into prepared crust and smooth surface with spatula. Transfer pie to oven and bake until custard is firm around the edges but center jiggles slightly, 25 to 30 minutes. Cool pie to room temperature, then cover with plastic wrap and chill at least 3 hours or overnight.