I have long been fascinated by lemon bars, and they’ve been on my ‘must bake’ bucket list for some time now. They are a quintessentially American treat, and something that I have heard lots about – mostly from American literature and TV shows – but they’re rarely seen or tasted in the UK.
Researching what looked like a reliable recipe for these was something of a challenge; it seems the variations on lemon bars are endless (some have a thin pastry, whilst others boast a thick shortbread base; some feature a no-bake, chilled curd, some a baked lemon custard), and every American cooking icon has their own beloved version, from Pioneer Woman to Ina Garten to the team at Bon Appétit.
For those of you who have never tried a lemon bar, the best way to describe them is probably as a slightly more robust tarte au citron, in traybake form. The base here is thin and melt in the mouth, with a sharp-sweet lemon curd-like topping. In short: they’re extremely delicious.
The recipe is largely based on one by the great Alice Medrich, but I’ve tweaked it ever so slightly to make it gluten-free and UK-measurement friendly. A copious dusting of icing sugar to finish is, of course, non-negotiable.
For the crust:
100g unsalted butter, melted
30g caster sugar
1 tsp vanilla extract
1/4 tsp salt
125g flour (I used Doves Farm gluten free plain flour + 1/2 tsp xantham gum)
For the topping:
250g caster sugar
25g plain flour
3 large, free-range eggs
Grated zest of 3 lemons, preferably unwaxed
Juice of 2 large lemons
Icing sugar, for dusting
- Preheat the oven to 180°C. Grease a 8 x 8 inch square metal baking tray and then line it with baking paper so that it overhangs (this will make it easier it lift the bars out of the tray).
- To make the crust, combine the sugar, vanilla, salt and melted butter in a medium bowl. Add the flour (and xantham gum, if using) and mix until incorporated, and you have a nice, soft dough. Press the dough evenly over the bottom of the tin, then bake for about 25 minutes until the crust is well browned at the edges and golden brown in the centre. When the crust is done, remove it from the oven and turn the oven temperature down to 150°C.
- Whilst the crust is baking, make the topping. In a medium bowl, whisk together the sugar and flour to combine. Next, whisk in the eggs until blended, followed by the lemon zest and juice.
- When the base is cooked, remove it from the oven and carefully pour the lemon mixture onto the warm crust, then return the tin to the 150°C oven. Bake for 20 to 25 minutes longer, until the topping is puffed at the edge and no longer jiggles in the centre. Transfer the tin to a cooling rack and let it cool completely. Once cooled, I like to transfer the tin to the fridge for an hour or so for the filling to firm up completely.
- Once completely cool, lift the baking paper liner out of the tin and transfer the bars to a cutting board. If the surface is covered with a thin layer of moist foam (not unusual), you can blot it gently with a paper towel (although if you’re covering the bars with icing sugar, this isn’t really necessary). Using a sharp knife, cut into bars and then dust liberally with icing sugar just before serving.
- The bars can be refrigerated in an airtight container for up to three days.