Clean the earthworms by washing them thoroughly in cold water. Then boil the earthworms 3 times, using clean water each time. Spread worms on a cookie sheet and bake them in a 180ºC oven for 10 to 15 minutes, or until worms are "crispy". Let worms cool and crumble like bacon bits. Combine egg, milk, salt and Worcestershire sauce in a bowl. Stir in cheese, sprinkle half of onions over unbaked crust then pour in half of the egg mixture. Top with the onions that are left. Bake at 180ºC for 30 minutes and allow to cool for 5 minutes before cutting.