I'm really excited about this tart. It’s my contribution to the evolutionary journey of the great British Bakewell tart, which was born when somebody in a pub kitchen made a mistake while making a Bakewell pudding. I’m using hazelnuts and walnuts in place of almonds to give the filling a wicked sort of praline flavour.
Sift the flour and half the icing sugar into a large bowl, then rub in the butter until the mixture resembles breadcrumbs. Mix in the zest of the orange, then add the beaten egg and a small splash of milk and mix together until you have a ball of dough. Don’t work it too much. Lightly flour the dough, wrap it in cling film, then chill in the fridge for 30 minutes. After that time, roll the pastry out on a clean floured surface until it’s about 0.5cm thick. Loosely roll it around the rolling pin, then unroll it over a 25cm loose-bottomed tart tin. Ease the pastry into the tin, pushing it into the corners. Trim off any excess overhanging pastry, wrap that in cling film and keep for use in another recipe. Prick the base of the tart all over with a fork. Cover with cling film and chill in the fridge for another 30 minutes.
Preheat the oven to 180°C/350°F/gas 4. Remove the cling film from the chilled base, then line it with scrunched-up greaseproof paper and dried rice. Blind bake for 12 minutes, then remove the paper and rice and bake for a further 5 minutes. Meanwhile, put a large pan on a medium heat and add the cranberries, sugar and the zest and juice from 11⁄2 oranges. Bring to the boil, then reduce to a simmer over a medium to low heat and cook for 15 minutes, stirring occasionally, until lovely and jammy. At this point, take the pan off the heat and leave to cool.
Blitz the nuts for the filling in a food processor until really fine. Tip into a clean bowl, then put the butter and sugar into the food processor and whiz until pale, creamy and fluffy. Grate the zest of the lemon and orange into the food processor, then crack in the eggs, one at a time, keeping the food processor running until well mixed. Tip the blitzed nuts back into the food processor along with the flour, and blitz again to mix. Set aside.
Spread a third of your cooled cranberry jam mixture over the base of your pastry case, then spoon over the frangipane and gently spread it out. Dot a few more blobs of cranberry jam on top, and put the rest of it aside (it will be delicious on toast and makes the perfect filling for jam tarts. Cook the tart in the hot oven for 45 to 50 minutes, or until golden and set. Once cooked, leave to cool for 20 minutes, then transfer to a wire rack while you make your icing.
Put the remaining icing sugar into a bowl, then squeeze in drops of juice from the zested orange and lemon until you have a nice thick drizzly mixture. Serve the tart drizzled with that zesty icing, and with a little dollop of cream, if you like.