Pi Day Special: Key Lime Pie (Wheat- and Egg Free)

Happy Pi Day, everyone! In celebration of this joyous affair, I am providing many pies, and today is the first of my three offerings: Key Lime Pie!

March the 14th is Pi Day, because in the American date system it's 3/14, and Pi is 3.14 (totes nerdy), and people on this day like to eat pie. In America also, pie tends to refer to dessert rather than dinner, whereas here in Ireland and the UK we tend to think of pie as something meaty.

I did a key lime pie a few years ago for Pi day, but I wasn't a big fan of the no bake version: I found the texture lacking. I've been researching online different ways of doing a key lime pie, and there are a few versions that are baked. Some include eggs, and others don't: in fact, the simplest version is just lime juice and zest mixed with condensed milk.

This version uses good old fashioned chemistry to set itself. If you mix something acidic with something dairy, it will curdle and thicken, which is how the no bake one works: you mix lime juice with condensed milk and boom you have something that's slightly custardy.

However, if you slightly heat the mixture it will set into something a little more curd-like. In the UK, there is a traditional dessert called posset, where heated cream is mixed with sugar and lemon juice to make something that sets kind of like panna cotta. In a key lime pie, the heating is done not on the stovetop, but in the oven.

The brief trip in the oven changes the texture into something much firmer and cut-able than a simply mixing the ingredients together and bunging them in the fridge.

This recipe I mixed condensed milk together with whipping cream to make it much less sweet, but if you like you can use all condensed milk.

INGREDIMENTS

For the crust

• 8 ounces (225 grammes) ginger biscuits or digestives, regular or gluten free
• 3 ounces (85 grammes) butter, at room temperature
• 2 ounces (55 grammes) caster sugar

For the filling

• One 14 ounce (397 gramme) can of condensed milk
• 6 fluid ounces (180 millilitres) whipping cream (about 30% fat)
• 4 fluid ounces (120 millilitres) lime or lemon juice
• Zest of one lime
• 2 teaspoons (10 millilitres) vanilla essence
• Good pinch of salt

To decorate,

• Whipped cream
• White chocolate, melted
• Sprinkles, crushed biscuits, or coloured sugar

HOW-TO

First, prepare the crust

• Preheat the oven to 180°C (350°F, Gas Mk.4), and find an 8 or 9 inch (20 or 22 centimetre) pie dish.
• Crush the biscuits into a fine sand using a food processor, or by rolling over the biscuits in a sandwich bag.
• Melt the butter in a medium sized saucepan and add in the biscuits, sugar, and salt. Mix until thoroughly combined.
• Press the crumbs into the base and sides of the dish, packing tightly, and bake in the oven for about 5 to 8 minutes.
• If the crust loses its shape during cooking, you can reshape it with a flat bottomed glass while it's still hot.
• Allow to cool completely before filling, which should take about half an hour

Then make the filling

• In a large bowl, mix together all the filling ingredients except the juice until completely combined and smooth.
• Add in the juice and mix thoroughly: the mixture will thicken rapidly as you mix in the acidic lime juice.
• Pour the filling mixture into the cooled crust and shake to level the top. Tap a few times on the work surface to release any bubbles.
• Return the pie to the oven at 180°C (350°F, Gas Mk.4) and bake for 15 minutes, or until the filling it set.
• Allow to cool to room temperature, then chill in the fridge for at least 4 hours, preferably overnight.

Now, assemble the masterpiece

• Cut out a small square of baking paper and stick it to a flat board with cellotape. Melt the white chocolate and draw out a Pi shape. While the chocolate is still wet, coat with sprinkles or another decoration. Allow to set completely, which will take about an hour.
• Decorate the top of the pie with whipped cream and the Pi symbol. Serve cold.

No blogs this time in previous years.