Stovetop Lemon Meringue Filling
Whisk lemon juice, sugar, cornstarch, and water over medium heat until thickened and translucent, then temper in egg yolks. Continue cooking until the mixture coats the back of a spoon, finish with butter, and pour into a pre-baked crust before topping with meringue.
Watch the temperature to keep the eggs smooth.
Control your heat carefully when adding the yolks to avoid scrambling them. Use a heavy-bottomed pot to ensure the cornstarch doesn't scorch at the base.
- heavy-bottomed saucepan
- whisk
- silicone spatula
- small mixing bowl
What goes in.
- 1 cupgranulated sugar
- 3 tbspcornstarch
- 1.5 cupswater
- 3large egg yolks, beaten
- 1/2 cupfresh lemon juice
- 1 tbsplemon zest
- 2 tbspunsalted butter
Bringing the eggs up to speed
Whisk a small amount of the hot, thickened cornstarch mixture into your cold egg yolks before adding them back to the pan. This prevents the proteins from setting instantly into curds.
The method.
Combine the dry ingredients and water
Whisk sugar, cornstarch, and water in your saucepan over medium heat until it begins to bubble and turn clear.
Temper the yolks
Take the pan off the heat. Scoop out half a cup of the hot mixture and whisk it quickly into the beaten yolks in a separate bowl. Slowly pour this yolk mixture back into the main pot.
Cook to thicken
Return to medium-low heat. Stir constantly for two minutes until it thickens significantly and loses the raw starch taste.
Finish the filling
Remove from heat. Stir in the lemon juice, zest, and butter until smooth and glossy. Pour immediately into your crust.
When it doesn't go to plan.
Pour the filling into the crust while it is still hot to ensure the meringue binds properly to the surface.
Use a fine-mesh grater for the zest to avoid bitter white pith.
If you see small lumps, push the filling through a fine-mesh sieve before pouring.
The ones that keep coming up.
Why is my filling runny?
You likely didn't cook the cornstarch long enough. It needs to reach a gentle bubble after the yolks are added to activate the thickening power.
Can I use bottled lemon juice?
Stick to fresh juice. Bottled versions contain preservatives that alter the clean, sharp flavor profile needed for the custard.