Green Bean and Mushroom Casserole with Crispy Fried Onions

Ingredients for Green Bean and Mushroom Casserole with Crispy Fried Onions

• 900g mixed wild mushrooms, trimmed, halved or quartered if large (about 1/2" pieces)

• 4 sprigs thyme, divided

• 60ml extra-virgin olive oil

• Kosher salt, freshly ground pepper

• 900g green beans (preferably haricots verts), trimmed, cut in half on the diagonal

• 2 tablespoons unsalted butter

• 80g finely chopped red onion

• 2 large garlic cloves, very thinly sliced

• 2 tablespoons plain flour

• 475ml double cream, divided

• 240ml low-sodium chicken or vegetable broth

• 2 dried bay leaves

• 1 1/2 teaspoons finely grated lemon zest (from 1 medium lemon)

• Canola or vegetable oil (for frying)

• 120ml fine-grind cornmeal

• 2 tablespoons cornflour

• 1 1/2 teaspoons paprika

• 1 teaspoon ground coriander

• 1 teaspoon ground cumin

• 1 medium red onion, thinly sliced into 1/8" rings crosswise with a mandoline or very sharp knife, separated into rings

• Kosher salt, freshly ground pepper

• A 3-quart (13x9") baking dish

Preheat oven to 425ºF. Line 2 rimmed baking sheets with parchment paper. Arrange mushrooms and 2 thyme sprigs in a single layer on prepared baking sheets. Drizzle with oil; season with 3/4 teaspoons salt and 1/2 teaspoons pepper. Roast mushrooms, stirring once and rotating pan halfway through, until lightly golden, crisp-tender, and liquid is evaporated (watch carefully as cook time can vary between types of mushrooms), 25–35 minutes. Remove sheets from oven and reduce oven temperature to 375ºF.

Meanwhile, cook green beans in a large pot of boiling generously salted water until crisp-tender, 3–5 minutes. Drain in a colander and rinse under cold water to stop cooking. Drain well, then layer on a rimmed baking sheet with paper towels and pat dry. Wipe pot dry.

Melt butter over medium-low heat in same pot. Add onion and garlic and cook, stirring occasionally, until tender, 5–8 minutes. Stir in flour and cook, stirring occasionally, until aroma is mildly nutty, 4–6 minutes. Add 45ml cream and stir well to combine. Repeat twice, then stir in remaining cream, broth, bay leaves, and remaining 2 thyme sprigs. Bring to a simmer and cook, stirring occasionally and scraping sides of pot, until sauce is the consistency of slightly thickened cream and coats the back of a wooden spoon, about 20 minutes (do not over-reduce). Discard thyme and bay leaves. Stir in zest, 1/2 teaspoons salt, and 1/4 teaspoons pepper.

Arrange beans and mushrooms in 3-qt. baking dish. Pour cream sauce over; stir to evenly coat. Bake casserole until sauce is thickened and bubbling around the edges, about 20 minutes.

Pour oil into a large wide pot or high-sided skillet to a depth of 1/2". Heat over medium-high until hot but not smoking (about 177°C on a deep-fry thermometer). Line a rimmed baking sheet with paper towels.

Whisk cornmeal, cornflour, paprika, coriander, and cumin in a large shallow bowl. Toss onion rings in cornflour mixture to coat.

Working in batches, fry onion rings, stirring and turning occasionally, until golden and crisp, 2–3 minutes. Using tongs or a slotted spoon, transfer to prepared sheet to drain. Season with salt and pepper while hot.

Arrange beans and mushrooms in a 3-quart baking dish. Pour cream sauce over; stir to evenly coat. Bake at 375ºF until sauce is thickened and bubbling around edges, about 20 minutes.

Top casserole with fried onions and serve warm.

Onions can be fried 1 day ahead. Let cool. Arrange in a flat layer on a paper towel-lined rimmed baking sheet, cover loosely with foil, and store at room temperature.

Green beans and mushrooms can be cooked 3 days ahead; keep chilled in separate airtight containers. Let come to room temperature before using.

Disclaimer

While every effort has been made to ensure the information is accurate and up to date, individual needs may vary and dietary requirements can differ based on personal health conditions. Always check food labels and allergen information before preparing or consuming any recipe. If you have specific health concerns, allergies, intolerances, or are following a medically prescribed diet, seek advice from your GP, pharmacist, or a registered dietitian before making significant changes to your diet or lifestyle.