Step 1

Arrange eight heatproof ramekins on a foil-lined baking sheet.

Step 2

In a large Dutch oven, melt the butter over medium heat. Add half the onions, cover and let cook for 3 minutes so they begin to wilt before adding the rest. Stir every few minutes for 35 – 40 minutes.

Step 3

When the onions are slightly browned, add 1 cup of the broth and stir up any caramelization on the bottom of the pan. Add the remaining broth and the bouquet garni. Reduce the heat to low and let the soup simmer for 15 minutes.

Step 4

Meanwhile, preheat your broiler to high.

Step 5

When the soup is ready, remove the bouquet garni, then carefully ladle some into each of the bowls. Add a splash of sherry to each bowl (no more than a teaspoon), add a crouton, and top generously with shredded cheese.

Step 6

Carefully place the baking sheet into your oven and broil until the cheese is melted and browned, which will take about eight minutes. (Keep an eye on it)

Step 7

Serve the soup immediately, while the cheese is still bubbling.