Melt 2 tablespoons butter in a large skillet over medium heat.
Add ½ finely diced white onion and cook until the onion is soft.
Stir in 2 teaspoons minced garlic and cook for 1 minute.
Add 2 drained cans of cut green beans, 1 can cream of mushroom soup, ¼ cup milk, ½ teaspoon salt, and ½ teaspoon pepper to the skillet.
Top with 1 can French fried onions.
Then top the casserole with the remaining French fried onions.
Move the pan to the oven and then broil for 2-3 minutes to brown the top of the casserole (watch closely to make sure that the top does not burn). Remove the casserole from the oven, allow it to sit for 5-10 minutes and then it’s ready to serve and enjoy!
Notes
This casserole is best served fresh but you can refrigerate the leftovers in an airtight container for up to 5 days. I love making this recipe in a cast iron skillet so that the pan can go from the stovetop to the oven. If you do not have a cast iron skillet, this can be made in a regular skillet and just skip the broiling of the top of the casserole.