Lime Meringue Tart

Ripe limes will yield a lot more juice than hard, underripe specimens. Like all citrus, when choosing them at the market, heft as many as you can (which in Paris, is normally interdit, although I try to sneak and do it anyways); the heaviest ones have the most juice. And be sure to squeeze limes that are at room temperature, rolling them firmly on the counter beforehand to rupture the juice sacs within to get as much juice out as possible. Lemon-lovers can substitute lemon juice for the lime juice and reduce the sugar by 1 tablespoon.

8 tablespoons (115g) butter, salted or unsalted, cut into pieces
3/4 cup (180ml) freshly-squeezed lime juice, from about 5-6 limes
3/4 cups (150g) sugar
zest of two limes, unsprayed (see Note)
pinch of salt
3 large egg yolks
3 large eggs
2 large egg whites
5 tablespoons (75g) sugar
pinch of salt
a few drops vanilla extract
One recipe, French tart dough, pre-baked, or another favorite tart dough

Preheat the oven to 375º (180ºC.)
In a medium-sized saucepan, warm the butter, lime juice, sugar, zest, and salt.
In a separate bowl, whisk together the eggs and the yolks.
When the butter has melted and the mixture is warm, gradually pour some of the warm lime juice mixture into the eggs, whisking constantly. Scrape the warmed eggs back into the saucepan and cook the mixture over low heat.
Stir the mixture constantly over low heat, using the whisk, until the filling thickens and begins to resemble soft jelly. Do not let it boil. (For the intrepid, you can do this step in a large bowl set over a saucepan of simmering water instead of over direct heat.)
Remove from heat and scrape the filling into the pre-baked tart shell.
Bake for 10 minutes.
To make the meringue (see Note for alternative method), whisk together the egg whites, sugar, and salt in the bowl of a stand mixer. Set the bowl over a pan of simmering water, and whisk it as it heats, checking it with an instant-read thermometer.
Once it reaches 140F (60C), transfer the bowl to the standing mixer and beat at high speed until cool, scraping down the sides once of the mixer bowl, midway during mixing, and add the vanilla. Whip until the meringue is light and fluffy.
Heat the broiler and move the oven rack to the top third of the oven.
Scrape the meringue into a pasty bag fitted with a star tip and pipe a ring around the perimeter of the tart. Or spread in a ring around the tart with a spatula.
Pop the tart under the broiler, watching carefully, as it will brown quickly. When the top begins to darken, remove the tart from the oven and cool completely before slicing.

Notes

Storage: The tart is best eaten the day it’s made. You can refrigerate any leftovers. If you wish to make the lime filling in advance, you can make it and store it in the refrigerator for up to five days.

Notes: If you’d like to make a standard meringue, you can simply whip the whites on high speed to soft peaks. Gradually add the sugar and the salt, while whipping on high speed, until the meringue is shiny and stiff. Beat in the vanilla, then pipe or spread over the tart.

A few people have inquired what I mean by “unsprayed” when referring to limes, and other citrus fruits. That means that the fruit is either organic, or grown in a manner where the outside hasn’t been sprayed with pesticides. Because you’re using the zest of the fruit, I think it’s a good idea to choose fruits that haven’t been treated in that manner. Depending on where you live, fruit may not be designated ‘organic’, because of the cost of certification, but may be labeled with another term: transitional, unsprayed, pesticide-free, and untreated. When in doubt, ask the produce supplier.