I had a bag of limes. I only wanted one, to make a salad dressing. But limes get lonely on their own. Or so the supermarkets would have you believe. And so I ended up with six. And even storing them in the fridge they were starting to look a little saggy. There’s only so many G&Ts you can drink before you have to get creative. So I Googled. Lime. Lime pie. Lime and chocolate? And lo and behold, my inquisitiveness was rewarded with the perfect dish I had been sort of considering, I just hadn’t realised it. A chocolate and lime tart, inspired by those chocolate lime sweets, like inside-out chocolate éclairs, with lime, not toffee. I’m not sure why it didn’t come to me before, it’s such a brilliant combination (I maintain the best choice to go for by the Trevi fountain, even with all those wonderful 50+ flavours in the ice cream shops there, is a simple duo of rich chocolate and lemon. Simple is always best).
It’s important to really ramp up the lime in this with zest and a hint of green food colouring. Just so your brain agrees with your mouth that it is indeed lime and not lemon or any other flavour (honestly, it’s amazing how much of an influence your eyes have on what you taste). And some ultra dark chocolate to get a really rich and bitter topping. I used half 70% and half 85% chocolate (does that make it 77.5% or does chocolate not work like that?). Use the best quality chocolate you can afford, it will make a big difference.
I was a little concerned about the amount of cornflour in the lime curd and when I cleaned out the saucepan at the end it felt a little powdery on the tongue. However, once set in the tart the texture was fine, a cross between a curd and a jelly, firm enough to cut but with a definite wibble to it. This should definitely be stored in the fridge, but won’t collapse if it’s left out of the fridge for an hour or two.
For the tart shell I used Dorie’s great unshrinkable tart shell recipe that bakes the shell from frozen. It works well, though requires a little more forward planning than you might have. Given that the shell is gluten free and therefore is impossible to overwork (yipee), it’s easier to just press the dough into the pan and distribute with your fingertips than rolling it out.
Unshrinkable tart shell
1 cup gluten-free flour blend
1/2 cup rice flour
Very scant 1/2 cup icing sugar
Pinch of salt
1 stick plus 1 tablespoon butter (125g)
1/4 teaspoon vanilla extract
Zest of two limes
Juice of 4 limes
Juice of 1 orange
Enough water to bring the liquid up to 360ml in total
200g caster sugar
3 egg yolks
2 tablespoons butter
3 drops green food colouring
100g 70% cocoa chocolate
50g 85% cocoa chocolate
150ml single cream
1. In a large bowl mix the gluten-free flour blend, icing sugar and salt together. Cut in the butter in small cubes and then rub into the flour with your fingertips until the mixture resembles coarse meal. Make a well in the centre of the mixture and stir in the vanilla extract and the egg. Stir with a fork until it starts to come together in a cohesive mass, then bring together with your hands.
2. When the dough is almost all in one mass, tip it out into a 9-inch tart tin and using your fingertips and the heel of your hand press the dough into the tart pan and up the sides. Make sure it is evenly spread over the whole tin. Transfer the tart tin to the freezer for at least 30 minutes or overnight.
3. When frozen press a piece of buttered foil, shiny side down, into the tart shell, wrapping tightly around the edges. Bake the tart shell in a preheated 180 C oven for 20-25 minutes, then remove the foil and return to the oven for a further 10 minutes, until golden brown in the centre and medium brown round the edges. Set aside to cool completely.
4. To make the lime curd juice 4 limes into a measuring jug. Add the juice of one orange and enough water to bring the total volume of liquid up to 360ml. Pour this into a medium saucepan along with the lime zest, cornflour, sugar and egg yolks. Stir thoroughly until the sugar and cornflour have dissolved into a paste and then bring to a simmer on a medium heat, stirring all the time. When the mixture starts to thicken up, leave it to simmer for another minute (stirring all the time), then add the butter and the food colouring. Simmer for another minute or two, still stirring constantly, until thick and gloopy, the texture of thick custard, then remove from the heat and spread into the cooled tart tin. Smooth the top over with the back of a spoon and move to the fridge to set for at least 30 minutes.
5. In another saucepan melt the chocolate with the cream over a low heat, stirring well. When the mixture has melted and completely combined remove from the heat and leave to cool for at least 10 minutes. When cooler, but not completely cold, spread over the top of the by-now set lime curd. Smooth with a knife and top with a couple more shavings of lime zest for decoration if desired.
6. Chill again in the fridge for at least 2 hours, or until the ganache is completely firm.
Serves many. Keeps in the fridge for 4 days, and that’s as far as it got.