Lemon Tart with Coconut Crust

In my neck of the woods, citrus is about the only fruit available during the frigid winter months.  And if I really didn't like citrus, I'd probably be mad about that.  Luckily I do like it--quite a bit in fact.  Its got that tart bite that I find refreshing during the bleak winter months--and they're tropical fruits that hint at the warmth from which they are borne.  And I fantasize about that warmth.  My all time favorite citrus dessert is key lime pie.  My ideal one has a tooth-achingly sweet and salty graham cracker crust that cuts up the key lime filling.    

I found a recipe for a key lime tart in Alice Medrich's Flavor Flours.  Unfortunately, I only had lemons on hand and no condensed milk so I couldn't make it.  But, I could use the recipe for the crust. Not surprisingly--since this particular recipe book explores baking using just about any flour other than wheat flours--it doesn't call for my beloved graham cracker crust.  Instead, it pairs itself with another tropical fruit, the coconut. Both shredded coconut and coconut flour join forces to create the base for this tart.  The result is essentially a crust that tastes like a macaroon.  And since the recipe for the crust is just about the same as one for macaroons, it's not all that shocking.  The only difference is that it uses coconut flour. I think macaroons are pretty amazing so eating a crust in the form of a giant one is by no means a chore.  

My only trouble with making this coconut crust was that it wasn't exactly the most structurally sound crust.  Macaroons are crispy on the outside and chewy on the inside.  But this crust was just chewy all over.  So when I cut into the tart, it was more pliable than anything else so I never got a clean cut.  I always ended up having to scrape off some of the crust from the bottom of the pan.  Nevertheless, I think that if I baked it a bit longer, that issue would have been resolved.  

In my mind, pairing two tropical fruits like this just seems to make perfect sense.  And truly, they go together well--it was an excellent crust.  I'm not saying I'm going to totally give up on a graham cracker crust for a key lime pie but it's certainly a nice alternative to have in your back pocket.  

Recipe

Crust via Alice Medrich's Flavor Flours

40g (1/3c) coconut flour
100g (1c + 1T) unsweetened shredded coconut
1/4 tsp baking powder
1/2 tsp salt
85g (6T) unsalted butter at room temp. and softened
100g (1/2c) granulated sugar
1 large egg white

First, preheat the oven to 350 F and then grease a 9 inch tart pan with a removable bottom.  Next, using a large bowl combine all of the ingredients together until everything is well incorporated. After that, press the mixture into the bottom and sides of the tart pan--making sure that every inch is covered well and that the sides of the pan are thicker than the base.  Place the tart pan on a baking sheet and bake it in the oven for at least 15 minutes.  I baked mine for 15 minutes and I felt that it wasn't done so maybe in the time range between 15-20 minutes depending upon your oven.  I would touch the bottom of the crust and if it seems fairly firm then it will probably be good.  Once, the crust has baked, remove it from the oven and let it cool completely before making the filling.

Filling

100g (1/2) granulated sugar
2T corn starch
1/8 tsp salt
1/2c water
1/4c milk
2 large egg yolks (save the whites for the meringue)
1T unsalted butter
1/4c fresh lemon juice
1 tsp lemon zest

First, preheat the oven to 350 F.  Then using a small bowl, whisk together the egg yolks until lighter in color and set it aside.  In a medium saucepan, combine the sugar, corn starch, salt, water and milk. Set the mixture over medium heat and whisk constantly until the mixture just comes to a boil. Remove the saucepan from the heat and pour about a third of the mixture into the egg yolks and quickly whisk to combine. Pour that mixture back into the saucepan with the rest of the milk mixture. Set it over low heat while whisking constantly and cook just until it thickens and it starts to slowly bubble. Remove it from the heat and add the butter, lemon juice and lemon zest and whisk to combine.  Place a piece of plastic wrap over the surface of the filling and set aside while you make the meringue.

Meringue

2 large egg whites
50g (1/4c) granulated sugar

In the bowl of a stand mixer using the whisk attachment, start whisking the egg whites on medium speed until they are foamy.  Then slowly start pouring in the sugar.  Whisk the whites on medium-high speed until stiff glossy peak form.  Set the meringue aside while you assemble everything.

Assembly

Pour the slightly cooled filling into the cooled tart shell and make sure it's evenly distributed.  Next, either spread the entire meringue over the tart or pour it into a piping baking with a plain tip and pipe any sort of design you wish.  Once that's done, bake the tart for about 12-15 minutes until it is set and the meringue peaks have just started to brown.  Remove the tart from the oven and let it cool completely before slicing into.