Grease your flan tin with butter and spread evenly your short crust pastry pressing it gently at the edges using a fork .Brush lightly with egg and place in the for about 15-20 minutes in the oven until it goes hard. Meanwhile, break the eggs into a jug or mixing bowl, add a little milk and give it a stir. Add half of the grated cheese, onion, ham & mushroom. Add a little pinch of salt and pepper (or any other seasoning you would like) Stir all of the ingredients together.Take the pastry out of the oven and pour your mixture evenly onto the base & sprinkle on the rest of the cheese and the pepperoni. Cook in the oven until it has risen and set. ( FOR ROASTED NEW POTATOES LOOK AT THE SIDES SECTION)