For the egg in the bacon nest, brush the ovenproof ramekins with melted butter. Press the bacon into the ramekins to form a nest.
Pour in the grated cheese and crack an egg on top of each, season with salt. Fold the overhanging strips of bacon in half so that the egg is covered by the bacon and enclosed as completely as possible.
Bake in the preheated oven at 190 °C for about 10 minutes. (The egg white should be set, but the yolk still slightly runny).