01 -
3 pounds yellow onions (4 large or 6 medium).
02 -
6 tablespoons unsalted butter, divided.
03 -
1 teaspoon dried thyme.
04 -
2 dried bay leaves.
05 -
2 1/2 teaspoons kosher salt, divided.
06 -
1/2 teaspoon black pepper.
07 -
3 medium carrots.
08 -
3 medium stalks celery.
09 -
3 cloves garlic.
10 -
2 pounds boneless skinless chicken breasts or thighs.
11 -
3/4 cup dry white wine.
12 -
1 tablespoon dry sherry.
13 -
1/4 cup all-purpose flour.
14 -
6 cups low-sodium chicken broth.
15 -
1/2 baguette (for toasts).
16 -
2 ounces Gruyère cheese (for toasts).