Ingredients
Equipment
Method
Prepare the casserole
- Drain and rinse the green beans, then let them drain thoroughly in a colander.
- Heat the oven to 350°F.
- Lightly grease a 9x13-inch baking dish with the canola oil.
Make the sauce
- Melt the butter in a 12-inch skillet over medium heat.
- Add the mushrooms, salt, and pepper and cook for 6 to 8 minutes, stirring occasionally, until the mushrooms are browned and their liquid has evaporated.
- Stir in the garlic and cook for 30 seconds.
- Stir in the flour and cook for 1 minute.
- Gradually whisk in the broth and milk, bring to a simmer, and cook for 3 to 5 minutes, whisking often, until the sauce is thick enough to coat the back of a spoon.
- Remove the skillet from the heat and stir in the cheddar until melted.
Assemble and bake
- Stir the drained green beans into the sauce.
- Transfer the mixture to the prepared baking dish and spread it evenly.
- Bake uncovered for 25 to 30 minutes, until the casserole is bubbling around the edges.
- Scatter the crispy fried onions evenly over the top.
- Bake for 5 to 8 minutes, until the onions are golden.
- Let the casserole rest for 5 minutes before serving.
Notes
Drain the green beans thoroughly so the casserole stays creamy rather than watery. Refrigerate leftovers for 3 to 4 days; freezing is not recommended because the topping loses its crispness. For a vegetarian version, use vegetable broth in place of chicken broth.
