If Meyer lemons are unavailable, substitute equal amounts of regular lemon juice and orange juice.
Makes 10 to 12 servings
1. Prepare Gingersnap Crust: Preheat oven to 350°. Stir together gingersnap crumbs and butter. Firmly press mixture on bottom and up sides of a 10-inch tart pan. Bake at 350° for 9 minutes or until golden and fragrant. Cool in pan on a wire rack 30 minutes.
2. Meanwhile, prepare Fresh Meyer Lemon Curd: Whisk together 1 1/2 cups sugar and cornstarch in a heavy saucepan. Whisk in eggs and egg yolks. Stir in lemon juice. Bring to a boil over medium heat, whisking constantly. Boil, whisking constantly, 1 to 1 1/2 minutes or until thickened. Remove pan from heat. Stir in lemon zest and butter.
3. Fill a large bowl with ice. Place pan containing lemon curd in ice, and let stand, stirring occasionally, 15 minutes. Spread lemon curd over prepared crust. Place heavy-duty plastic wrap directly on lemon curd (to prevent a film from forming); chill 2 hours. (Mixture will thicken as it cools.)
4. Prepare Italian Meringue: Preheat broiler with oven rack 8 inches from heat. Combine 1/4 cup water, 1 cup sugar, and corn syrup in a small heavy saucepan; cook over medium heat, stirring constantly, until clear. Cook, without stirring, until a candy thermometer registers 240° (soft ball stage).
Beat egg whites at high speed with an electric mixer until soft peaks form; slowly add syrup mixture, beating constantly. Beat until stiff peaks form. Spoon meringue in center of tart; spread to within 2 inches of edge of tart. Broil 3 to 4 minutes or until golden brown. Cool completely on a wire rack. Chill 1 hour.