Key Lime Tart

Key Lime Pie.... Creamy.... Cool.... Tart.... Refreshing.... A universally appealing dessert for the warm days of Spring and Summer.... And my mother's request for dessert this past Mother's Day.

While delicious, it was frankly not an obvious choice for a blog post. There must be hundreds of blog posts written on Key Lime Pie. But as I looked through post after post, I saw that all of the fillings were variations on the classic filling made with sweetened condensed milk. And while there is nothing wrong with that particular filling...it is not the one that I make. Instead, I make mine with a delicious key lime curd.

The recipe I use is not my own. I found it several years ago in Emily Luchetti's dessert cookbook Four Star Desserts. It is nearly identical to my recipe for lemon curd—which is probably why I noticed it in the first place. It is fast, easy and truly delicious. I have only changed her recipe in one respect: I bake the curd filled tart briefly before chilling it. This helps give the filling a firmer set—guaranteeing beautiful clean slices.

Most of the time when I make this tart, I go to the trouble of squeezing fresh key limes. This is admittedly a bit of a pain, but I have always assumed that it was worth it (isn't fresh always better?). But since this popular pie (or tart) is frequently made with bottled juice, I have often wondered if the fresh lime juice was really that much better.

On Mother's day I had a perfect opportunity to make a side-by-side comparison. My family is large, so in order to feed them all, I needed to make two tarts. I made one with freshly squeezed juice and one with bottled.

The two tarts cooling...  you can't tell the difference by looking....

I freely admit that the one made with bottled juice was very good. But I really did like the one made with fresh juice better. It was more tart (important, since limes are supposed to be tart), but more importantly it was more aromatic...I don't know any other way to describe it. The bottled juice tart tasted like a slightly faded copy in comparison—acceptable in a pinch...but inferior none-the-less.

If you have never tasted a key lime pie (or tart) made with fresh key limes, you should try it at least once.  And if the only filling you have ever had is the one made with sweetened condensed milk, you should definitely give this one—made with fresh key lime curd—a try.

Key Lime Tart

1 1/2 c. sugar
1 t. lime zest
3/4 c. strained key lime juice (this will take about 1 lb. of limes)
4 eggs
4 oz. (1 stick) unsalted butter, cut into pieces
1 9-inch pre-baked graham cracker crust (see below)

1 1/2 c. whipping cream
3 T. sugar
3/4 t. vanilla

Combine the sugar, zest and key lime juice in a medium saucepan and bring to a boil over high heat. In a medium-sized bowl, whisk the eggs until homogenous. When the syrup boils, whisk it into the eggs in a thin stream. Return this mixture to the saucepan and place over medium heat. Stir constantly until the mixture is visibly thickened—this will only take about 3 minutes. Remove from the heat and whisk in the butter, piece by piece.

When the butter is fully incorporated, strain the curd into the graham cracker crust. Place on a baking sheet and bake in a 350° oven until set (it will still be a bit wobbly, but it won't be liquid-y)—15 to 20 minutes. Let the tart cool before transferring to the refrigerator to chill until cold.

Combine the whipping cream, sugar and vanilla. Whip until soft peaks form. Swirl over the tart.

Chill for an hour or so. Sprinkle some of the reserved crumbs over . Cut into wedges and serve. Serves 8 to 10.

(Recipe adapted from Emily Luchetti's Four Start Desserts)

Graham Cracker Crust:
1 1/4 c. (120 g) graham cracker crumbs
1/4 c. sugar
1/2 t. cinnamon
2 oz. (4 T.) unsalted butter, melted

Combine dry ingredients. Add the melted butter, stirring until the mixture is homogenous. Set aside 2 Tablespoons of the crumbs. Press the remaining crumbs into a greased, removable-bottom 9-inch tart pan, covering the sides and the bottom evenly. Bake in a pre-heated 350° oven until beginning to brown—10 to 12 minutes. Set aside.

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