White Bean Casserole with Crunchy Onion Topping

White Bean Casserole with Crunchy Onion Topping

By An Edible Mosaic

I used white beans and did my own version of a crunchy onion topping, made with a flavorful mixture of sautéed onion and breadcrumbs.

Actually, when I set out making this dish, I had my White Bean Chowder in mind as inspiration, and was trying to remake that soup into a side dish. Funnily enough, the end result tastes much less like that soup and much more like a classic French dish called Cassoulet. It's a rich and hearty, almost stew-like casserole; perhaps a bit unconventional for a Thanksgiving side, but it would be a delicious addition to a holiday dinner nonetheless.

Ingredients for the Crunchy Onion Topping:

  • 3 Tbsp unsalted butter

  • 1 medium-large onion, finely diced

  • ¼ tsp dried thyme leaf

  • ¼ tsp salt

  • ⅛ tsp black pepper

  • 1 large clove garlic, minced

  • ½ cup panko bread crumb

  • 2 Tbsp minced fresh parsley


  1. For the topping, heat the butter in a large skillet over medium heat; add the onion and cook until softened but not browned, about 5 to 7 minutes, stirring occasionally. Add the thyme, salt, black pepper, and garlic, and cook 1 minute, stirring constantly. Add the breadcrumbs and cook until light golden brown, about 5 minutes, stirring occasionally. Turn off heat and stir in the parsley; set aside for now.

Ingredients for the Casserole:

  • 1 Tbsp butter, plus more to grease the dish

  • 1 Tbsp olive oil

  • 2 slices turkey bacon, finely diced

  • 1 medium onion, diced

  • 2 large carrots, diced

  • 2 large stalks celery, diced

  • ½ medium red bell pepper, diced

  • 3 cloves garlic, minced

  • ½ tsp dried thyme leaf

  • ¼ tsp dried crushed oregano

  • ¼ tsp salt

  • ⅛ tsp black pepper

  • 1 bay leaf

  • 1 ½ Tbsp flour

  • 2 cup low-sodium vegetable or chicken stock

  • 2 Tbsp tomato paste

  • 16 oz can no-salt-added cannellini beans or other white beans


  1. For the casserole, heat the butter and oil in a large skillet over medium-high heat; add the turkey bacon and cook until crispy, about 3 minutes, stirring occasionally. Turn heat down to medium and add the onion, carrot, celery, and bell pepper; cook until starting to soften, about 5 minutes, stirring occasionally. Stir in the garlic, thyme, oregano, salt, black pepper, and bay leaf and cook 1 minute, stirring constantly. Stir in the flour and cook 1 minute.

  2. Add the stock, tomato paste, and beans and bring to a boil; turn heat down and simmer (uncovered) until the veggies are tender and the sauce is thickened, about 10 to 15 minutes, stirring occasionally. Mash a few of the beans against the side of the pot.

  3. Preheat oven to 400F; grease an 8 by 8-inch baking dish with butter. Pour the bean mixture into the dish and top with the Crunchy Onion Topping; bake 10 minutes and serve hot.

To Reheat: Preheat oven to 350F; cover the dish with foil and bake until hot throughout, about 20 minutes.

Additional Serving Suggestion for Crunchy Onion Topping: Use as a topping for any casserole, or sprinkle on top of salad or soup in place of croutons.

Yield: 8 to 10 side dish servings, or 4 main-course servings

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