2 tablespoons olive oil or unsalted butter
2 medium yellow onions, diced
3 medium carrots, diced
2 stalks celery, diced
kosher salt and pepper
3/4 cup fresh flat-leaf parsley, finely chopped
2 teaspoons fresh thyme
1 day-old baguette, cut into 1/2-inch pieces (about 8 cups)
3 cups low-sodium chicken broth, warmed
Heat oven to 400 F.
Heat the oil in a large skillet over medium heat. Add the onions and cook until golden brown, about 8 minutes. Add the carrots and celery and cook until soft, about 6 minutes. Add 1 1/2 teaspoons salt, 3/4 teaspoon pepper, the parsley, and thyme and cook for 1 minute.
In a large bowl, combine the bread, vegetables, and broth. Transfer to a baking dish. Bake for 20 minutes, until heated through.