Key lime and lemon tart

Key lime

The Key lime is a citrus species with a globose fruit, 2.5–5 cm in diameter. It's yellow when ripe but usually picked green commercially. It is smaller and has more seeds, a higher acidity, a stronger aroma, and a thinner rind, than that of the Persian lime. It's valued for its unique flavour compared to other limes, with the Key lime usually having a more tart and bitter flavour. The name comes from its association with the Florida Keys, where it is best known as the flavouring ingredient in Key lime pie. It's also known as West Indian lime, bartender’s lime, Omani lime, or Mexican lime, the last classified as a distinct race with a thicker skin and darker green colour. Philippine varieties have various names, including dayap and bilolo.

Key limes are much smaller (ping-pong to golfball-sized) than Persian limes, nearly spherical, thin-skinned, and often contain a few seeds. Green key limes are actually immature fruits, prized for their acidity. As they ripen to a yellow color, the acid content diminishes greatly, resulting in a sweeter fruit.

Fresh Key lime is preferred for flavoring fish and meats, marinades , making limeade, and garnishing drinks and plates due to its tantalizing bouquet and unique flavor.

Key lime and lemon tart

Ingredients

  • 250g Granita or wheatmeal biscuits, crushed
  • 1/4 cup of roasted almonds finely crushed
  • 60g unsalted butter, melted
  • 3 egg yolks
  • 400g can sweetened condensed milk
  • Juice and rind of one large lime (3 small ones if large ones unavailable) and one large lemon
  • 400g can sweetened condensed milk
  • 3 egg whites.

Method

  • Preheat oven to 160°C
  • Grease a 23cm loose-bottomed tart pan
  • Combine the crushed biscuit, crushed almonds and melted butter in a bowl
  • Press mixture onto the base and sides of the greased pan
  • Refrigerate for 15 minutes while you make the filling
  • Beat the egg yolks with a whisk until thick
  • Slowly stir in the condensed milk
  • Add the lime and lemon juice and rind, whisking well to combine
  • Use a clean whisk to whip the egg whites until stiff
  • Fold stiffened egg whites into the lime mixture
  • Pour into the tart pan then bake in the oven for 20-25 minutes. (The filling will still have a slight wobble but will firm on cooling.) 
  • Set aside to cool, then refrigerate.

European meringue

Ingredients

  • 315g (1 1/2 cups) caster sugar
  • 60ml (1/4 cup) water
  • 3 egg whites, at room temperature
  • Pinch of cream of tartar.

Method

  • Stir sugar and water in a saucepan over low heat until sugar dissolves, brushing pan with a wet pastry brush
  • Cook on medium-high heat (don’t stir) for 3-5 minutes or until the syrup is 115ºC (soft ball stage)
  • While the syrup is cooking, whisk the egg whites and cream of tartar until soft peaks form
  • When syrup is 121ºC (hard ball stage), slowly add to egg white mixture
  • Whisk on high speed until thick
  • Spoon the meringue onto the baked pie
  • Use a flat-bladed knife to make large swirls to create peaks
  • Use a blowtorch to caramelise the meringue, or bake in oven at 200ºC for 5 minutes or until browned.

Sofia's suggestion

  • Instead of European meringue, you could decorate with fresh cream, adding thinly sliced lime and lemon.

Information, recipe and image source

Background info on Key limes and key lime image: en.wikipedia.org
Recipe: Valli Little and modified by Sofia Moutzouris
Key lime tart image: Sofia Moutzouris
Key lime image: en.wikipedia.org.