The 5 Onion Soup
2 leeks, white and light green parts only, thinly sliced
1 stick unsalted butter
1/4 cup plus 2 tbsp extra virgin olive oil, divided
2 white onions, thinly sliced
2 red onions, thinly sliced
6-8 shallots (about 3/4 pound), chopped
2 bunches scallions, thinly sliced
1/4 cup all purpose flour
1 qt chicken stock
1 1/2 cups heavy cream
1/4 cup dry Marsala or red wine
1 tbsp Morton kosher salt
1/2 tsp white pepper
2/3 cup finely grated parmesan cheese
16 fresh basil leaves, torn
1 tbsp worcestershire sauce
1 tsp tabasco sauce
8 slices ciabatta or baguette
8 slices Gruyere cheese
Wash the leeks thoroughly. Melt the butter with 1/4 cup olive oil in a Dutch oven or heavy-bottomed pot over medium heat. Add the leeks, onions, shallots, and scallions, stirring and coating them well with the fat.
Decrease the heat to low, and slowly cook, stirring occasionally, until they are all melting but not showing any color – about an hour.
Stir in the flour until it’s completely incorporated. Add the cream, stock, Marsala, salt, and white pepper. Increase the heat to medium and simmer until it is rich and thick – another 30 or so minutes. Stir regularly to keep flour from scorching.
When the soup is very thick, stir in the Worcester, Tabasco, Parmesan, and basil.
Meanwhile, make the croutons. Heat the oven to 400°F. Drizzle bread slices with reserved olive oil and toast in the center of the oven until very crisp.
Ladle soup into bowls, layer croutons over soup and place provolone cheese on top. Place under broiler and broil until cheese is speckled brown.