• Thinly slice the onions then set aside. Add the butter and olive oil to a Dutch oven or soup pot over medium-low heat.
• Once the butter has melted, add the onions, thyme, salt, pepper and grated garlic then gently stir to combine so the onions are coated with the butter-olive oil mixture.
• Cover and cook 15 minutes, stirring occasionally and checking to make sure they aren't burning. 
• Increase the heat to medium-high, add the brown sugar and continue to cook for about 30 minutes or until the onions are completely caramelized. 
• Reduce the heat to medium/medium low then sprinkle in the flour. Stir to combine and cook 2-3 minutes or until a paste forms.
• Pour in the wine and Worcestershire sauce then continue cooking over medium-low heat about 5 minutes as the wine reduces.
• Add the beef stock stirring to make sure the flour is completely blended then add the bay leaf. Cover, bring to a boil over medium-high heat then reduce the heat and simmer 30 minutes. Taste and adjust salt (I have added as much as 1 more teaspoon of salt, a little a time tasting after each addition).

Cheesy Croutons

• Slice the baguette into 1" slices then brush olive oil onto both sides and transfer to a baking sheet (cooking spray can also be used). 
• Lightly toast both sides then divide the grated cheese between the slices. Return to the broiler until the cheese is melted and bubbly.

To Serve

• Ladle the soup into bowls and top with cheesy croutons. Serve hot.