• Yield: Serves 10

For our Slow-Cooker Green Bean Casserole recipe, we tested frozen beans, fresh raw beans, and blanched fresh beans, and were happy to learn that fresh beans held up well in the slow cooker. We didn’t even bother with the canned stuff. Sautéing the mushrooms before adding them to the slow cooker prevented them from turning slimy. It also gave us the idea to build the whole sauce in the skillet to reduce it and concentrate its flavor. Ground-up fried onions bound our sauce and also added more onion flavor than merely sprinkling them on top

We suggest French’s French Fried Onions and Swanson Certified Organic Free Range Chicken Broth for this recipe. Fresh green beans are essential—frozen beans will turn to mush in the slow cooker.



  • 1 cup canned fried onions (see note)

  • 3 tablespoons unsalted butter

  • 10 ounces white or cremini mushrooms, cut into 1/4-inch-thick slices

  • Salt and pepper

  • 4 garlic cloves, minced

  • 1/2 teaspoon dried thyme

  • 1/4 cup all-purpose flour

  • 1 1/4  cups low-sodium chicken broth (see note)

  • 1 1/4  cups heavy cream

  • 2 pounds green beans, trimmed and cut into 1-inch pieces


  • 2 slices hearty white sandwich bread, torn into pieces

  • 2 tablespoons unsalted butter, melted

  • 2 cups canned fried onions


1. Make Sauce: Pulse canned fried onions in food processor until finely ground; set aside. Melt butter in large skillet over medium heat. Add mushrooms, 3/4 teaspoon salt, and 1/2 teaspoon pepper, and cook until mushrooms release their liquid, about 5 minutes. Increase heat to medium-high and cook until liquid has evaporated, about 5 minutes. Stir in garlic and thyme and cook until fragrant, about 30 seconds. Add flour and ground onions and cook until golden, about 1 minute. Stir in broth and cream and bring to boil. Reduce heat to medium-low and simmer, stirring occasionally, until sauce is very thick and creamy, about 10 minutes.

2. Slow-Cook: Combine sauce and green beans in slow cooker. Cover and cook on low until beans are tender, 5 to 6 hours.

3. Toast Topping: Meanwhile, pulse bread and butter in food processor until coarsely ground. Toast bread crumbs and onions in clean skillet over medium-high heat until golden brown, 3 to 5 minutes. Top green beans with bread-crumb mixture. Serve.

MAKE AHEAD: Sauce and topping can be refrigerated in separate airtight containers for 2 days. To finish, microwave sauce, covered, for 1 minute before proceeding with step two. Crisp breadcrumb mixture in skillet before topping beans.

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