Blitz the flour, butter and sugar in a food processor. Add 1 egg yolk and blitz again. The pastry should come together into a ball. If not, add the second yolk and 1-2 tsp cold water. Shape the pastry into a disc. Wrap the disc and leave to rest in the fridge for about 45 mins.

Roll the pastry out into a circle on a lightly floured piece of baking parchment. It needs to be about 5cm bigger than a 25cm tart tin with a loose-bottomed base.

Use the rolling pin to lift the pastry and line the tin with it. Push it into the sides of the tin all the way round, then cut off the excess. Chill in the freezer for 30 mins.

Heat the oven to 180C/160C fan/ gas 4. Fill the case with crumpled baking parchment and baking beans, then blind-bake the pastry case for 20 mins. Remove the beans and paper, then bake for another 15 mins. Take the tart case out and leave to cool in the tin. Increase the heat to 200C/180C fan/gas 6.

Meanwhile, for the filling, put the apples into a saucepan with the porter. Bring to a simmer and cook for 5-8 mins until the porter has reduced by about half. Put this in a bowl with the breadcrumbs, oats, citrus zests and lemon juice.

Warm the golden syrup in a pan over a low heat with the butter and a pinch of salt. Leave to cool, then whisk in the cream and eggs. Mix this into the rest of the filling.

Spoon the filling into the tart case, then bake for 40 mins, or until the surface is dark golden and the filling seems just set when you press the centre (it will continue to set as the tart cools). Serve warm with some whipped double cream.