Start by making the pastry. Sift the flour and salt into a bowl. Add the butter and rub into the flour mixture. Add the oil and mix. Add the sugar, lemon zest and vanilla. Mix and then add enough chilled water to be able to knead the mixture to a firm dough. Turn onto a floured surface and knead for 2 minutes. Wrap in cling film and stand for 30 minutes in a cool place. Grease a dove shaped baking pan with butter and dust with flour. Cut a sheet of aluminum foil and grease with butter. Roll out the pastry over a lightly floured surface and line the base and sides of the prepared pan with the pastry. Prick the pastry with a fork, and place the greased aluminum sheet buttered side down over the pastry. Lightly press the sheet over the pastry and also cover the edges of the pastry. Spread butter beans to act as weight evenly over the foil. Bake in a moderate to hot oven for 20 minutes. Bring out of oven, remove the foil and beans and leave to cool. Spread the apricot jam on the base of the pastry shell. Beat the butter and sugar until pale and fluffy. Add the eggs one by one while beating continuously. Beat in the ground almonds and almond essence. Fold in the flour and mix well. Pour the mixture into the baked pastry shell and smooth the surface. Bake in a moderate oven until risen and lightly browned. Bring out of the oven and stand for 20 minutes before turning out of the pan. Leave to get cold. Decorate with a sprinkling of icing sugar and the slivered almonds.

Suggested accompanying wine: DELICATA Casella Mscato Sweet White wine