Ruby's Lemon and Basil Tart

We were invited to a friend’s barbecue on one of the hottest days of the year. The hosts needed a dessert so I searched through my cookbooks for something suitably summery. I settled on Ruby Tandoh’s Lemon and Basil Tart, from her cookbook Crumb.

If you don’t have Tandoh’s book and you’re interested in baking, I recommend it. She started out on the Great British Bake Off, but was quickly snapped up by the Guardian to write a column for their Saturday Cook supplement. She competed on Bake Off while studying for her degree in philosophy and art history, for which she received a first. The lady is obviously smart and she brings all her intelligence to what is essentially a baking bible covering cakes, bread, sweet dough, biscuits, puddings, desserts, pies, tarts and pastries, with thorough advice on everything from perfect whisking to all the different bread flours. It’s thoughtful, considered, beautifully designed and very pretty.

So, I set aside the morning to bake the tart. It might not have been the best day to attempt shortcrust pastry, and it took a lot longer than expected – I ended up using the freezer to chill the pastry as the fridge just wasn’t cutting it – but I got there in the end and the result was a refreshing, gooey lemon tart with a hint of basil and a rich, crumbly pastry.

And I’m glad I made the effort. One of the barbecue hosts is a budding chef with a dream to open a deli, and she was assisted by a former chef at Heston Blumenthal’s pub, The Crown at Bray (the jerk chicken he prepared was the best I’ve tasted – and I live in Brixton). So my (Ruby’s) tart had some big acts to follow, but everyone loved it. It was the perfect dessert for a hot summer’s day.

Here’s how I made it.

Serves 8 (it’s pretty rich so mine probably served twice that many)

For the pastry:

175g plain flour

90g butter, firm but not cold (I only had salted in the fridge, if you use unsalted add a pinch of salt)

1 tbsp caster sugar

1 large egg yolk

1 tbsp milk

For the filling:

200ml double cream

a few basil leaves

4 large eggs

125g caster sugar

zest and juice of 5 small lemons (125ml juice)

First rub together the flour and butter until you have fine breadcrumbs, then add the sugar (and salt, if using).

Beat the egg yolk with the milk and slowly add it to the flour mixture. Bring the dough together (I needed an extra teaspoon of milk, probably because it was such a hot day), flatten it into a disc and wrap it in cling film. Refrigerate for 30 minutes (I needed to put mine in the freezer for 15 minutes afterwards).

Put the cream and basil leaves into a pan over a medium heat and bring to

a boil, then immediately take it off the heat and leave it to infuse.

Roll out the chilled pastry and line a tart dish, with a small overhang. Trim it back and press the pastry up the flutes of the dish so that it’s slightly higher than the rim (this allows for any shrinkage while it’s baking). My pastry was pretty crumbly so I patched up a couple of thin spots with the excess pastry, then it went back in the freezer for 15 minutes.

Line your pastry case with baking paper and beans and blind bake for 15 minutes at 200°C/180°C fan/gas 6, then removed the paper and beans and cook for another 5 minutes. (Mine needed an extra 5 minutes.) Take the tart out of the oven and reduce the heat to 150°C/130°C fan/gas 2. My pastry had cracked a little at the edges so I used a little more of the excess pastry to patch it up again.

Lightly whisk the eggs and beat in the sugar. Strain the cream into the mixture and discard the basil leaves. Add the lemon zest and juice and whisk to combine. Pour the mixture into the tart case (set it on the oven shelf halfway through and pour the last of the mixture in while it’s stable in the oven, that way you lessen the risk of spilling it) and bake for 25–30 minutes (again, mine needed an extra 5 minutes), until the edges of the filling are firm but the centre wobbles (it will firm up as it cools).

Ruby tweets @rubytandoh. Crumb is published by Chatto & Windus.