The Best French Onion Soup Recipe Ever

Ok, so seriously is it just me or are most french onion soups too salty.  I'm hoping this isn't the case!
Hubby's favorite french onion soup is at Lewis & Clark's restaurant in St. Charles, MO.  So, hopefully, he'll enjoy this one, since STC is 4.5 hours away...

We shall see...

Best French Onion Soup Recipe
Adapted from America’s Test Kitchen
Ingredients:

• 4 lbs yellow onions
• 3 tablespoons butter
• 1/2 cup sherry
• 4 cups chicken broth
• 2 cups beef broth
• 1 bay leaf
• sprig of thyme
• water
• salt
• pepper
• toasted baguette slices
• grated or thinly sliced cheese (any combination of gruyere, swiss, jarlsbeg, and parmesan)

1. Preheat your oven to 400 degrees. 
2. Spray the inside of a dutch oven with nonstick cooking spray, or pour some oil into the bottom and spread it all around with a paper towel. Cut the butter into smaller pieces and scatter it around the bottom of the dutch oven. Cut the onions in half through the root end, and slice into 1/4 inch thick slices from pole to pole. Put the slices of onion into the dutch oven and sprinkle 1 teaspoon of salt over the top. Cover the dutch oven and place it into the oven for 1 hour.
3. Remove the dutch oven after an hour and take off the cover (use oven mitts!), stirring the onions and scraping down the sides. The onions should just be starting to brown. Replace the cover on the dutch oven but leave it slightly ajar cook for another hour. Stir and scrape down the sides again, then put it back in the oven with the cover still ajar for another 45 minutes.
4. Remove the pot and place it on the stove over a medium high heat. Stir frequently and scrape down the sides. After 15 minutes, a dark crust should form at the bottom of the dutch oven. Don’t be alarmed! This is fond, and it’s full of flavor. It can get to be a very dark brown, just watch that it doesn’t get too black or burned. Turn down the heat if necessary. After the fond is formed, pour in 1/4 cup of water and scrape the fond up from the bottom, stirring it into the onions. After the water has evaporated, cook the onions for another 6-8 minutes until another fond crust forms at the bottom of the dutch oven. Add another 1/4 cup of water and scrape it up from the bottom, mixing it into the onions. Repeat this process 4 times in total. The onions will be very brown and soft at this point – that’s a good sign!
5. After the fourth scraping, let the fond develop one more time, then deglaze with 1/2 cup of sherry. Scrape up all the brown bits and mix it with the onions. At this point the onions should be a very dark, deep brown color.
6. Pour in 2 cups of water and both the chicken and beef broths. Add in the bay leaf and a sprig of thyme. Stir to combine, then turn the heat up to high. When the soup starts to boil, cover the dutch oven and turn the heat to low. Simmer for 30 minutes. Taste and adjust for seasoning, adding salt and pepper as needed.
7. To prepare the soup for serving, toast slices of baguette. Ladle some hot soup into an oven safe bowl and cover the top of the soup with the toasted baguette. Top the baguette slices with cheese. Gruyere is the classic preference but I like to use a combination of jarlsberg and parmesan. Place the bowls of soup on a cookie sheet and side it under the broiler. Watch it very carefully as the cheese bubbles and browns very quickly.
8. Remove the bowls from the oven very carefully and place on plates to serve. The bowls are super hot so be careful! Let it cool down a bit but be sure to eat it while it’s hot and the cheese is melted and stringy.