Dinner

Creamy Green Bean Casserole from Scratch Recipe

ByJeannette Jaeger December 13, 2025December 13, 2025

Introduction

Discover how to make a creamy green bean casserole entirely from scratch, using fresh vegetables and a homemade gravy sauce. This recipe skips the canned soups and relies on simple ingredients for a rich, comforting dish perfect for any occasion.

A white rectangular baking dish contains a green bean casserole with three visible layers: the bottom layer is creamy and white, the middle layer is bright green cooked green beans mixed with a light brown mushroom sauce, and the top layer is a thick, crispy golden-brown fried onion topping that covers most of the casserole but shows some of the green beans beneath on one side. The casserole sits on a white marbled surface with a striped beige and white cloth to the left alongside a pile of silver forks, and in the top right corner, there is a white plate with some fried onions on a spoon. Photo taken with an iphone --ar 4:5 --v 7

Ingredients

1 medium onion
1/2 cup (62g) all-purpose flour (spooned & leveled)
3/4 cup (45g) panko breadcrumbs
1/2 teaspoon salt
1/4 teaspoon ground black pepper
1 large egg
1 Tablespoon (15ml) milk
1 Tablespoon + 1 teaspoon salt, divided
1 pound fresh green beans, rinsed, ends trimmed, and halved
2 Tablespoons (28g) unsalted butter
8 ounces sliced mushrooms
1/2 teaspoon ground black pepper
2 cloves garlic, minced
2 Tablespoons (15g) all-purpose flour
3/4 cup (180ml) chicken or vegetable broth
1 and 1/4 cups (300ml) half-and-half

Instructions

Step 1: Preheat the oven to 450°F (232°C). Line a large baking sheet with parchment paper or a silicone baking mat and set aside.
Step 2: For the baked onions, thinly slice the onion and separate the slices. Place flour in one bowl, mix panko with salt and pepper in another, and whisk the egg with milk in a third bowl.
Step 3: Using one hand for dry and one for wet, dip onion slices first into flour, then egg mixture, and finally coat well with panko mixture. Arrange on the baking sheet.
Step 4: Bake the onions for about 20 minutes until golden brown, flipping them twice during baking. Set aside when done. Reduce oven temperature to 400°F (204°C).
Step 5: Blanch the green beans by boiling a gallon of water with 1 Tablespoon salt. Add green beans and cook for 5 minutes. Transfer immediately to an ice water bath to stop cooking. Drain and set aside.
Step 6: Melt butter in a large ovenproof skillet over medium-high heat. Add mushrooms, 1 teaspoon salt, and pepper; cook until mushrooms release moisture, about 5 minutes.
Step 7: Stir in garlic and cook 2 minutes more. Sprinkle flour over the mixture and stir until combined and flour absorbs moisture.
Step 8: Add broth and simmer for 3 minutes. Reduce heat to medium-low, add half-and-half, and cook until sauce thickens, about 10 minutes.
Step 9: Remove skillet from heat. Stir in a quarter of the baked onions and all the green beans until combined.
Step 10: If not using an oven-safe skillet, transfer mixture to a greased 2–3 quart casserole dish. Top with remaining baked onions.
Step 11: Bake at 400°F (204°C) until bubbling around the edges, about 15 minutes. Serve warm.

Tips & Variations

Use vegetable broth for a vegetarian version.
For extra crunch, add chopped toasted almonds over the top before baking.
Make the baked onions ahead of time and store in an airtight container to save prep time.
For a richer sauce, substitute heavy cream for half-and-half.

Storage

Store leftovers in an airtight container in the refrigerator for up to 4 days. Reheat gently in the oven or microwave until warmed through, stirring to maintain creamy texture.