A popular Southerner's dish, this Oyster Casserole was also known as oyster dressing, oyster pie or even scalloped oysters depending on where you lived. Recipes also varied but there were a few consistencies: oysters, a rich and creamy sauce, and a crispy topping. I've tried many and this one is hands down, mouth wide open... the best!
- 5 tablespoons salted butter, divided
- 1/4 cup yellow onion, chopped
- 1/4 cup green bell pepper, chopped
- 1/4 cup celery, chopped
- 2 scallions, thinly sliced
- 1 teaspoon garlic, minced
- 2 (16-ounce) containers fresh oysters, drained well
- 4 ounces fresh mushrooms, sliced (about 1 1/2 cups)
- 2 tablespoons all-purpose flour
- 1/2 cup heavy cream
- 1 ounce Parmesan cheese, grated (about 1/4 cup)
- 3/4 teaspoon kosher salt
- 1/4 teaspoon black pepper
- 1/4 teaspoon ground nutmeg
- 1 cup coarse fresh breadcrumbs (from 1/4 baguette)
Adapted from southernliving.com
Melt 2 tablespoons of the butter in a skillet over medium-high. Add onion, bell pepper, celery, scallions, and garlic. Cook, stirring, until vegetables soften, 5 to 7 minutes.
Add oysters and mushrooms. Bring to a simmer, and cook, stirring often, 5 minutes. Set aside.
Melt 1 tablespoon of the butter in a small saucepan over medium. Whisk in flour, and cook, whisking constantly, until smooth, 30 seconds to 1 minute. Add cream, and cook, whisking constantly, until very thick and beginning to bubble. Add Parmesan, and cook, whisking constantly, until cheese is melted. Remove from heat.
Using a fine wire-mesh strainer, strain oyster mixture; discard liquid. Add oyster mixture to cheese sauce; stir until fully incorporated. Stir in salt, pepper, and nutmeg. Spread mixture in a lightly greased (with cooking spray) 11- x 7-inch baking dish. Melt remaining 2 tablespoons of butter; toss breadcrumbs with melted butter. Sprinkle breadcrumbs over oyster mixture.
Broil on middle rack of oven until breadcrumbs are deep golden brown and mixture is bubbly, 4 to 5 minutes.