Lemon Meringue Pie Parfaits

1. Stage

For the graham cracker crust: In a small bowl, stir together graham cracker crumbs and melted butter.

2. Stage

For the lemon curd: In a medium metal bowl, whisk together egg yolks and sugar until smooth, about 1 minute. Add lemon juice and zest to egg mixture and whisk until smooth. Once water is simmering, reduce heat to low and place bowl on top of saucepan. (Bowl should fit on top of saucepan without touching the water.)

3. Stage

Whisk until thickened, about 10 to 15 minutes, or until mixture is pale yellow and coats the back of a spoon. (It should feel thick as you pull your whisk through it and the trail of the whisk shouldn’t disappear immediately.) Remove from heat and stir in butter, 1 tablespoon at a time, allowing each to melt before adding the next.

4. Stage

Press through a fine sieve strainer, then pour strained curd into a bowl. Cover tightly with plastic wrap (so close it's touching the curd) and refrigerate until cool, 1 hour.

5. Stage

For the meringue: Fill a medium saucepan with 1" water and bring water to a simmer over medium heat. In a metal bowl (use the bowl of your stand mixer if you have one), whisk together egg whites, sugar, and cream of tartar. Place bowl over simmering water. and whisk constantly until sugar is dissolved and whites are warm to the touch, 3 to 3 1/2 minutes. (Test by rubbing between your fingers: there should be no grittiness from the sugar.)

6. Stage

Transfer bowl to electric stand or hand mixer fitted with the whisk attachment and whip, starting on low speed, gradually increasing to high until stiff, glossy peaks form, about 10 minutes. Add vanilla and mix until combined.

7. Stage

To assemble: Spoon cooled lemon curd into a piping bag fitted with a round tip. Spoon meringue into a different piping bag fitted with a star tip. Among four parfait glasses, layer graham cracker crumbs, lemon curd, and meringue. Repeat. Serve immediately. (If you have a kitchen torch, torch the top of the meringue to toast it!