1. Unnecessary or over-elaborate act or execution of a simple task
2. Squandering or inefficient use of valuable resources
3. Eggs en Cocotte (slang)
On reflection, he realised the he had made a real 'Finchley Breakfast' of what should have been a very simple Saturday morning task. He wrote to all his friends and family to apologise and went to think long and hard about what he had done.