Method

For the pâté sucrée, add the flour, butter, sugar and salt to a food processor and blend to a fine crumb. Use a fork to lightly beat the egg and then add to the food processor and pulse to bring the pastry together.

Wrap in clingfilm and chill for 1 hour in the fridge. To make the butterscotch sauce, place the butter, sugar and golden syrup in a saucepan over a medium heat, stirring to dissolve the sugar. Continue to cook to a smooth and shiny syrup. Carefully add the cream (as it will splutter) and stir to combine. Bring to a gentle bubble then simmer for 3 minutes. Add the rum and remove from the heat.

Preheat the oven to fan 160°C / fan 325°F / gas mark 4.

Roll out the pastry to 2-3mm / 0.1in thick and use to line a 23cm / 9in flan tin. Chill for at least 30 minutes in the fridge. To make the walnut filling, gently mix together the walnuts, sugar, butter, honey, egg yolks, cream and rum in a large bowl. Pour the mixture into the prepared pastry and bake in oven for 50-60 minutes or until golden brown and set with a slight wobble. Allow to set for at least 1 hour before serving with the butterscotch sauce and if desired some vanilla ice-cream.