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Dairy-free Southern green bean casserole made with oat milk and olive oil

Southern Green Bean Casserole

This Southern green bean casserole bakes tender beans in a from-scratch mushroom cream sauce with a buttery bite and a browned onion topping. It is weeknight easy, holiday worthy, and ready in about 45 minutes with pantry staples.
Servings 8 servings
Prep Time 20 minutes
Cook Time 25 minutes
Resting Time 10 minutes
Total Time 45 minutes

Equipment

  • 9x13 inch casserole dish
  • Large skillet

Ingredients

  • 2 pounds fresh green beans trimmed and cut in 2 inch pieces or use 2 pounds thawed frozen cut beans to save prep time
  • 3 tablespoons unsalted butter for sautéing and flavor
  • 1 tablespoon olive oil helps prevent butter from scorching
  • 8 ounces cremini or button mushrooms finely chopped for savory depth
  • 1 small yellow onion finely diced sweetness builds the sauce
  • 2 garlic cloves minced aromatic backbone
  • 3 tablespoons all purpose flour for thickening the gravy
  • 1 cup low sodium chicken stock or strong vegetable stock for body
  • 1 cup half and half or whole milk plus 2 tablespoons cream richer, silkier finish
  • 1 teaspoon kosher salt plus more to taste balances beans and dairy
  • 1/2 teaspoon black pepper warmth without heat
  • 1/2 teaspoon paprika optional gentle color and sweetness
  • 1 teaspoon soy sauce or Worcestershire savory boost and color
  • 1 cup shredded sharp cheddar optional Southern comfort tilt
  • 1 1/2 cups crispy fried onions divided classic top and a little inside for crunch
  • Pinch cayenne optional small lift without making it spicy

Instructions

  • Heat oven to 375 F and lightly butter a 9 by 13 inch casserole dish visual cue is a thin glossy coat that prevents sticking.
  • Blanch beans in salted boiling water 4 to 5 minutes until bright green and just tender then drain and shock under cold water to stop cooking beans should bend without snapping and still squeak slightly.
  • Make the base heat butter and oil in a large skillet over medium add onion and mushrooms and cook 6 to 8 minutes until mushrooms release liquid and edges brown golden bits on pan mean flavor.
  • Add garlic cook 30 seconds until fragrant sprinkle flour over and stir 1 minute to cook off raw taste mix should look pasty and glossy.
  • Whisk in stock slowly then half and half season with salt pepper paprika soy sauce and optional cayenne simmer 3 to 4 minutes to a spoon coating consistency a clean line should hold when you drag a finger on the back of a spoon.
  • Fold in beans 1/2 cup fried onions and cheddar if using taste and adjust salt the mix should taste slightly saltier than you want after baking.
  • Transfer to the dish and top with remaining fried onions bake 18 to 22 minutes until bubbling at the edges and onions are deep golden if onions darken too fast tent loosely with foil.
  • Rest 10 minutes before serving sauce thickens as steam settles and the scoop should hold its shape with a creamy trail.

Notes

Condensed soup shortcut replace flour stock and dairy with 2 cans condensed cream of mushroom and 1/2 cup milk for a classic back‑pocket version. No mushrooms increase onions to 2 cups and add a splash more soy sauce for umami. Cheesy bake swap cheddar for pepper jack for gentle heat or skip cheese for a lighter, mushroom‑forward profile. Gluten free use 3 tablespoons rice flour or cornstarch slurry added after the simmer to thicken then bake as directed. Make it meaty fold in 1/2 cup crisped diced smoked beef or pastırma for salty depth. Seasonal twist stir in 1/2 cup chopped toasted pecans and a little lemon zest for winter brightness.
Calories: 210kcal
Course: Side Dish
Cuisine: Southern
Keyword: Casserole