From America's Test Kitchen Season 4: Pot Roast
We love traditional green bean casserole, but we wanted a streamlined technique for preparing the dish—one with tender beans in a tasty sauce worthy of a holiday spread and yet speedy enough for a last-minute supper.
Rather than using two pots—one for the beans and one for the sauce—we cooked both in just one pot, a skillet. First, we built a sauce in the skillet with onion, garlic, chicken broth, cream, and a little flour; then we added the beans along with thyme and bay leaves, covered them, and allowed them to steam until the beans were almost done. We then stirred in meaty browned cremini mushrooms and thickened the sauce by uncovering the skillet during the final phase of cooking. And instead of canned fried onions, we sprinkled crunchy fried sliced shallots over our easy, tasty skillet casserole.