Author Adapted by Pam - For the Love of Cooking / Original by America's Test Kitchen
Equipment
8-inch baking dish
Food Processor
Large skillet
Large saucepan
Ingredients
Topping:
1½slicesof white sandwich breadtorn into large pieces
1tbspbutter
Sea salt and freshly cracked pepperto taste
1½cupsFrench's fried onions
Casserole:
1½tbspbutter
½lbbutton mushroomsstems trimmed and chopped into 1-inch chunks
¼yellow oniondiced
1cloveof garlicminced
1½tbspflour
¾cupchicken brothor vegetable broth for vegetarian
¾cupheavy cream
Sea salt and freshly cracked pepperto taste
1lbgreen beanstrimmed and halved
Instructions
Preheat the oven to 425 degrees. Lightly coat an 8-inch baking dish with olive oil cooking spray.
Make the topping by placing the torn bread, butter, sea salt, and freshly cracked pepper, to taste in a food processor. Pulse 10 times to get nice buttery crumbs. Pour the crumbs into a dish then add the French's fried onions and mix until well combined; set aside until needed.
Make the creamy mushroom sauce by heating the butter in a large skillet over medium-high heat. Add the mushrooms and onion and cook, stirring occasionally, for 6-7 minutes. Add the garlic and cook, stirring constantly for 1 minute.
Whisk in the chicken broth and heavy cream and bring to a boil; reduce heat to medium and cook for 5-6 minutes, until reduced and thickened. Taste the sauce then season with sea salt and freshly cracked pepper, to taste. Remove from the stovetop and set aside until needed.
Blanch the green beans in a large saucepan of well-salted boiling water for 5-6 minutes, or until crisp-tender. Immediately plunge the green beans into a large bowl filled with ice water to stop the cooking process. Side Note: If you are using haricot verts (French green beans), they will only need to blanch for a few minutes.
Dry the green beans by placing them on a few paper towels to soak up the water. Side Note: You don't want wet green beans diluting your delicious creamy mushroom sauce!
Prepare the casserole by adding the dried green beans to the creamy mushroom sauce and mix until well combined. Pour the mixture into the prepared baking dish.
Sprinkle the topping evenly on top, making sure to not press it down too firmly.
Place into the oven to bake for 13-15 minutes, or until the topping is golden brown and the mushroom sauce is bubbling.
Remove from the oven and allow to cool for 5 minutes before serving. Enjoy.