You can prepare the spinach mixture ahead and time and then reheat in the morning, crack the eggs and bake. The dish can be served with or without the hollandaise sauce.
At this point, you can divide the spinach mixture between two individual pans, or you can make 4 small wells using the back of a spoon and crack the 4 eggs into the wells. Bake for 6-8 minutes, just until whites are set. Serve alone or with hollandaise sauce and a dash of cayenne pepper.