Step 1

Place a large saucepan over medium heat and add the butter and olive oil.

Step 2

Once the butter has melted add the onions and cook until completely caramelized and golden brown, stirring from time to time for about 1 hour. Also, add a bit of water or Guinness to deglaze the pan as needed to prevent burning.

Step 3

Next, add the garlic, brown sugar, and thyme. Cook until fragrant, about a minute.

Step 4

Add the butter, let it melt, sprinkle and mix in the flour and let it cook for 2-4 minutes.

Step 5

Add the beer and deglaze the pan.

Step 6

Add the broth, Worcestershire sauce, mustard, bay leaves, salt, and pepper. Bring the mixture to a boil, reduce the heat and simmer for 30 minutes.

Step 7

Finally, ladle the soup into oven-proof bowls and arrange them onto a baking sheet.

Step 8

Top with the sliced bread and sprinkle cheese on top, broil until cheese melts, about 1-3 minutes. Serve.