Preheat the oven to 400°F, and lightly grease a 9 x 13 - inch baking dish.
Bring a large pot of salted water to boil. Cook the green beans for 5 to 7 minutes, just enough to soften them. Drain the water, and pour the green beans into the prepared dish.
2 pounds fresh green beans
In a medium saucepan, melt the butter over low-medium heat. Add the onions, and cook until they’re soft and translucent (about 5 minutes). Then add the garlic and cook an additional 30 seconds. Next, whisk in the flour, and continue to cook for 2 to 3 minutes.
½ cup white onion, 2 garlic cloves, 2 tablespoons unsalted butter, 2 tablespoons all-purpose flour
Pour in the chicken broth, and whisk until smooth. Then add the milk and heavy cream. Whisk until the mixture begins to thicken (about 5 to 7 minutes). Add salt and pepper to taste, and remove from heat.
¾ cup milk, ½ cup low-sodium chicken broth, ¾ cup heavy cream
Pour the sauce over the green beans, then top with French fried onions.
6 ounces French fried onions
Bake for 15 to 20 minutes. Cover with foil for the last 5 to 7 minutes if necessary to prevent the onions from over browning.
Serve warm, and store leftovers in the refrigerator for up to 3 days.
Notes
*The calories listed are an approximation based on the ingredients and a serving size of about 1/2 a cup of the fresh green bean casserole. Actual calories will vary.