Preheat oven to 220ºC (200ºC fan assisted)/425ºF/Gas M 7.
Roll out pastry to a rectangle approx. 40 x 30 cm or 14 x 12”. Then cut in half to get 2 rectangles of approx. 20 x 30 cm/7 x 12” each).
Spread half the tapenade over one pastry piece, fold in the long edges by approx. 2 cm/3/4”, continue to do this twice more, brush pastry with beaten egg then press the two sides together to give a long ‘roll’. Wrap in cling film and chill in fridge. Repeat with second half of pastry.
With a sharp knife, cut the rolls on the diagonal into approx. 18 slices per roll, lay cut side up on baking sheet and glaze with beaten egg. Bake for 10-12 minutes until golden brown and risen, serve warm.