Magic Lemon Pie

Preheat oven to 325°F. Gather all ingredients.

Break cookies into large pieces and place in a food processor bowl; pulse until fine crumbs, about 10 pulses. Add melted butter; pulse until mixture resembles wet sand, about 5 pulses. Transfer to a 9-inch pie plate; firmly press into bottom and up sides of pie plate. Refrigerate, uncovered, until ready to use.

Whisk together sweetened condensed milk and egg yolks in a large glass or other nonreactive mixing bowl until smooth. Add lemon juice; whisk until thick and creamy. Pour into prepared crust, smoothing out top with an offset spatula.

Bake in preheated oven until filling is just set with a slight jiggle in center, 20 to 25 minutes.

Meanwhile, beat together cornstarch, cream of tartar, and remaining egg whites with an electric mixer fitted with whisk attachment on high speed until foamy, about 10 seconds. Gradually add sugar, 1 tablespoon at a time, beating until stiff peaks form and sugar dissolves, about 4 minutes. Add vanilla, beating until just combined. Set aside, at room temperature, until ready to use.

Spread meringue over hot filling, ensuring filling is fully covered and meringue is touching crust. Increase oven temperature to 375°F. Bake at 375°F until meringue is golden brown, 10 to 12 minutes.

Let pie cool to room temperature on a wire rack, about 1 hour. Refrigerate, uncovered, until fully chilled before serving, about 4 hours.