Soupe à l'oignon gratinée, may take a bit of time, but the process is simple and you'll be amazed at how much flavor you can get out of some simple onions.
When the onions are sticky, glossy, and a medium brown, add the sherry. Deglaze the pan by scrapping up all the browned bits from the bottom of the pot and reduce again, until the onions are sticky, glossy and dark brown (about 10 minutes). Add the beef stock, demi glace, marjoram, bay leaf, then salt and pepper When salting, keep in mind the soup will reduce a bit when you're melting the cheese on top, so don'make it too salty. Let this simmer for about minutes for all the flavors to meld to taste.
Ladle the onion soup into broiler safe ramekins, crocks, or mini cocottes (there should be enough soup for 4-6 individual servings depending on the size of your bowls). Don'fill the containers all the way. Top with the soup with slices of toasted bread and push them into the soup. Top the soup with a generous helping of cheese.