method
1. First make the almond paste, a day ahead if possible.
2. Mix together the ground almonds and sugar and beat to a smooth paste with the butter and egg. Beat in the rum. Cover and leave to chill and harden.
3. Reserve two-thirds of the puff pastry, wrap in plastic film and leave in the refrigerator. Roll the remainder on a floured board, into a 20 cm (8 in) circle. Trim the edge cleanly with a sharp knife. Run cold water over a large, flat baking sheet to moisten it and shake off the excess. Transfer the pastry circle to it, cover and chill for 30 minutes.
4. Smooth the hardened lump of almond paste over the pastry to within 2.5 cm (1 in) of the edge, and lightly brush water on the border. Roll out the remainder of the pastry to twice the thickness of the base, and trim the edges cleanly, as before. Carefully fold the pastry circle over the rolling pin and lay it on top of the almond filling.
5. Press all round the edge firmly to seal the two layers together. Using a sharp, pointed knife dipped in hot water, cut a scalloped border. Cover and chill for 30 minutes.
6. Brush all over the tart top with beaten egg, cut a hole in the centre and insert a small, buttered aluminium foil chimney in it. Brush a second coat of egg glaze all over.
7. The decoration is distinctive and traditional. Using a pointed knife, cut into the pastry about 2 mm (1/8 in) deep. Inscribe lines radiating from the middle to the scalloped edge in a curved half-moon shape. Prick right through the pastry to the baking sheet in about six places.
8. Bake in the preheated oven at 230°C (450°F) Gas 8 for 15 minutes then reduce the temperature to 200°C ( 400°F) Gas 6 and bake for a further 30-40 minutes.
9. About 10 minutes before the cooking time is complete, sprinkle the top of the cake generously with sifted icing sugar and return the cake to the oven for it to caramelize.
10. The cooked cake should have puffed right up into a dome and be golden in colour. Lift out of the oven, remove the foil chimney and leave to cool on the baking sheet set on a wire rack.
rate this recipe