Preheat oven to a moderately hot 200c. Lightly grease 2 trays of 12 flat bottom patty pans. Cut the pastry sheet in half and lay one portion onto a surface dusted lightly with plain flour.
Roll the pastry until it measures 33 x 25cm. Cut 12 circles from the pastry using a 7.5 cm cutter. Press into the bases of lightly greased pans. Repeat with the remaining pastry.
Combine the eggs with the ham, green onion, milk, cheese and herbs. Spoon this mixture between cases and top each with a cherry tomato slice. Then bake for 12-15 minutes or until set and golden. Cool and store in an airtight container.