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Ultra close-up macro food photography of slow-cooker creamy green bean casserole with bubbly garlic cream and crispy fried onions

Slow-Cooker Creamy Green Bean Casserole with Crispy Onions

The ultimate stress-free Thanksgiving and holiday side dish made completely from scratch in the slow cooker. Crisp-tender fresh green beans and sautéed cremini mushrooms bathed in a rich, velvety garlic parmesan cream sauce, topped with a mountain of golden, shatteringly crisp French fried onions.
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Prep Time 15 minutes
Cook Time 3 hours
Total Time 3 hours 15 minutes
Servings: 8 servings
Calories: 245
Ingredients Method Nutrition

Ingredients
  

Fresh Green Beans & Mushrooms
  • 2 lbs fresh green beans trimmed and snapped; fresh beans stay crisp-tender
  • 10 oz cremini mushrooms adds savory umami richness
  • 3 tbsp unsalted butter for sautéing aromatics
  • 4 cloves garlic
  • 1 medium shallot sweet and aromatic
Velvety Garlic Parmesan Cream Sauce
  • 3 tbsp all-purpose flour thickens the homemade mushroom cream sauce
  • 1.5 cups broth warm halal broth
  • 1 cup heavy whipping cream for rich velvety comfort
  • 1/2 cup parmesan cheese adds salty savory depth
  • 1 tsp soy sauce secret flavor booster that replaces canned soup flavor
  • 1/8 tsp ground nutmeg classic French sauce touch
  • 1 tsp salt and pepper
Crispy French Fried Onion Topping
  • 2 cups French fried onions divided: 1/2 cup folded inside, 1 1/2 cups piled on top
  • 1/2 cup sharp white cheddar optional, for bubbly golden finish
  • 1 tsp fresh thyme for garnish

Method
 

Sautéing the Mushroom Aromatics
  1. Melt 3 tbsp butter in a large skillet over medium-high heat. Add sliced mushrooms and diced shallot. Sauté for 5 to 6 minutes until mushrooms are deeply caramelized and tender.
  2. Add minced garlic and cook for 1 minute until fragrant. Sprinkle flour over the mushrooms and stir constantly for 1 to 2 minutes to cook off the raw flour taste.
  3. Slowly pour in broth and heavy cream while whisking continuously. Bring to a gentle simmer for 3 minutes until a thick, glossy cream sauce forms. Stir in grated parmesan, soy sauce, nutmeg, salt, and black pepper. Remove from heat.
Assembling the Slow Cooker
  1. Lightly grease the insert of a 5 to 6-quart slow cooker with butter or cooking spray.
  2. Place the trimmed fresh green beans into the slow cooker. Pour the warm homemade mushroom cream sauce over the green beans. Fold in 1/2 cup of crispy French fried onions so they infuse into the sauce.
  3. Toss gently with a spoon until all green beans are evenly coated in the rich cream sauce.
Slow Cooking to Perfection
  1. Cover the slow cooker with the lid. Cook on LOW for 2.5 to 3 hours (or on HIGH for 1.5 to 2 hours) until the green beans are crisp-tender (tender to the bite but not mushy). Stir once halfway through.
Crisping the Onion Crown & Serving
  1. Sprinkle the shredded white cheddar cheese (if using) and remaining 1 1/2 cups of crispy fried onions evenly over the top of the casserole.
  2. To keep the onions shatteringly crisp: either prop the slow cooker lid slightly open and switch to WARM for 15 minutes, OR transfer the casserole into an oven-safe dish and broil at 400°F (200°C) for 3 to 4 minutes until bubbling and golden-brown.
  3. Garnish with fresh thyme leaves and serve hot directly from the slow cooker!

Nutrition

Serving: 1gCalories: 245kcalCarbohydrates: 18gProtein: 6gFat: 17gSaturated Fat: 9gCholesterol: 45mgSodium: 480mgPotassium: 380mgFiber: 4gSugar: 4gVitamin A: 920IUVitamin C: 15mgCalcium: 140mgIron: 1.5mg

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