Preheat the oven to moderately hot 200C/400F/Gas 6.
Cut the egg tomatoes in half lengthways and place them cut side up on a non stick baking tray.
Sprinkle with sea salt and freshly cracked black pepper.
Bake for 30 minutes, or until the tomatoes are tender; remove and set aside to cool slightly.
To make Pesto: Place the basil leaves, chopped garlic, pine nuts and grated Parmesan in a food processor.
Process until the mixture forms a smooth paste.
Gradually add the olive oil with the motor running.
Process until combined.
Cut each bocconcini in half.
Cut the sheet of pastry into quarters.
Place a spoonful of pesto in the center of each pastry square and spread with the back of a spoon, leaving a 2 cm (3/4 inch) border.
Arrange 3 tomato halves and 3 bocconcini halves decoratively on top of the pesto.
Brush the border lightly with the beaten egg.
Bake on a non-stick baking tray for 15 minutes, or until the pastry is puffed and golden and the bocconcini is melted.
Preparation : 20minutes
Cooking : 45 minutes
Bocconcini is the name given to small fresh mozzarella cheese. It was originally made from buffalo milk, but
is now made from cows milk. Buy bocconcini that are white in color; avoid any that show any sign of yellowing. Store in the whey they are sold in until ready to use.