I first heated the oven to 200 °C (390 °F), or 180 °C if using a fan oven. While it heats, I beat the egg and milk in a bowl until the mixture is smooth. Then I added salt and pepper well so the base flavour is there from the start.
Next, I greased my baking sheet, set two egg rings on it, and pressed the crumpets inside the rings so they fit snugly. I poured the egg-milk mixture over the top of each crumpet (inside its ring), making sure the liquid fills the holes. Then I sprinkled the grated cheese evenly over each one.
I popped the tray into the oven and baked for about 7-10 minutes. I watched for the edges of the cheese to bubble and for the egg around the crumpets to look set and slightly golden. After baking, I let them cool a little, removed the egg rings carefully, and added fresh parsley and a pinch of extra black pepper before serving.