This green bean casserole with mushrooms brings a sophisticated Spanish twist to one of America's favorite Thanksgiving side dishes. Some traditions are simply too good to change, but a few carefully chosen ingredients can make them even more memorable.
Tender green beans are coated in a rich homemade mushroom sauce, enhanced with the earthy flavors of Boletus and Truffle Spread by Rosara. A golden layer of crispy onions adds the perfect finishing touch.
Unlike traditional versions made with canned condensed soup, this homemade casserole develops its flavor from sautéed mushrooms, cream and Spanish gourmet ingredients. It is comforting, elegant and surprisingly easy to prepare.
Serves: 6-8 | Prep: 20 minutes | Cook: 35 minutes | Total: 55 minutes
Ingredients
- 1½ lb (680 g) fresh green beans, trimmed
- 8 oz (225 g) cremini mushrooms, sliced
- 3 tablespoons Rosara Boletus and Truffle Spread
- 2 tablespoons Oro Virgen extra virgin olive oil
- 2 tablespoons unsalted butter
- 2 garlic cloves, minced
- 3 tablespoons all-purpose flour
- 1 cup (240 ml) Aneto chicken broth or vegetable broth
- ¾ cup (180 ml) heavy cream
- ½ cup (120 ml) whole milk
- 1 teaspoon fresh thyme leaves
- 1½ cups crispy fried onions
- Salt and freshly ground black pepper, to taste
How to Make Green Bean Casserole with Mushrooms, Boletus & Truffle
Step 1. Blanch the green beans
Heat the oven to 375°F (190°C). Bring a large pot of salted water to a boil and cook the beans for 3-4 minutes, until bright green and just tender.
Transfer them to ice water to stop the cooking. Drain very well and pat dry to prevent a watery casserole.
Step 2. Make the boletus-truffle sauce
Heat the olive oil and butter in a large skillet over medium heat. Brown the sliced mushrooms for 6-8 minutes, until most of the moisture evaporates.
Add the garlic and thyme and cook for 1 minute. Stir in the flour and cook for 1 minute more. Gradually whisk in the broth, cream and milk.
Simmer for 3-5 minutes, stirring frequently, until thickened. Stir in the Rosara Boletus and Truffle Spread and season to taste.
Step 3. Assemble and bake
Gently fold the beans into the sauce, then transfer to a lightly greased baking dish. Bake uncovered for 20 minutes, or until bubbling.
Add the crispy fried onions and bake about 5 minutes longer, until the topping turns golden. Serve hot.
Cooking Tips
- Pat the beans dry after blanching so the sauce stays creamy.
- Brown the mushrooms properly before adding the flour for better depth of flavor.
- Add the crispy onions at the end rather than from the start to keep them crunchy.
Why Boletus & Truffle Make This Thanksgiving Casserole Special
The secret to this elevated green bean casserole with mushrooms is the combination of boletus and truffle. Made in Navarra, Spain, Rosara's gourmet spread combines boletus mushrooms, shiitake mushrooms and black truffle in a rich, creamy preparation.
A few tablespoons add depth and complexity to the sauce without requiring a long list of ingredients.
Good to know: the spread is made with beef broth and cream, so this casserole is not vegetarian, even if you use vegetable broth. Check the labels of all products for allergens; the recipe contains milk and wheat.
Make-Ahead Thanksgiving Tip
Blanch the beans and make the mushroom sauce the day before. Assemble without the crispy onion topping, cover and refrigerate.
Bake at 375°F (190°C) for 25-30 minutes until hot throughout, and add the onions for the final 5 minutes.
What to Serve with Green Bean Casserole
Serve it next to roast turkey, cranberry sauce, Manchego mashed potatoes and Spanish-style bread stuffing with chistorra. For another vegetable side, try our roasted Brussels sprouts with ham.
Frequently Asked Questions
Can I make green bean casserole without canned soup?
Yes. This recipe builds its sauce from mushrooms, flour, broth, milk, cream and Rosara boletus-truffle spread.
How can I keep my casserole from getting watery?
Blanch the beans briefly, cool them in ice water, then drain and dry the green beans thoroughly.
When should I add the fried onions?
During the last 5 minutes in the oven, so they stay golden and crisp.
Find more ideas in our Thanksgiving recipes.
