Homemade Green Bean Casserole

Preparation

Once you go all the way homemade green bean casserole, you’ll never want it another way again. Whipping up a homemade bechamel, flavored with lemon, garlic and Parmesan, is easy in the HexClad Hybrid Saucepan, with curved edges that make for easier whisking. There’s no need to use canned soup again. And let's not forget the topping. The crispy fried onions are so incredibly good, you'll be sneaking handfuls of them before they even make it onto the casserole. They add the perfect savory crunch that elevates this classic dish to a whole new level.

*This recipe originally ran in the US on HexClad.com.

1. Preheat oven to 375°F/190°C.
2. Prep the beans. Fill a HexClad 8 QT/7.5 L Hybrid Stock Pot with 4 in/10 cm water and bring to a boil over high heat. Place green beans in HexClad Steamer Basket and set in the pot. Cover and steam until beans are crisp-tender, about 5 minutes. Transfer to a HexClad Small Hybrid Roasting Pan or HexClad 9” x 13” Roasting Pan and spread in an even layer to cool. Season with salt and pepper. 
3. In a HexClad 10”/25cm Hybrid Fry Pan, heat oil over medium-high heat. Add mushrooms and cook, stirring occasionally, until they release their juices and start to brown, about 5 minutes. Add butter and thyme, season with salt and pepper and continue to cook until deeply browned, another 5 minutes. Scatter over beans in roasting pan. 
4. Make the bechamel. In a HexClad 2 QT/2L Hybrid Saucepan, melt butter over medium heat. Add flour and cook, whisking constantly, until lightly toasted and fragrant, 2 to 3 minutes. Gradually pour in half and half, whisking constantly. Increase heat and bring to a simmer, whisking often, until sauce is thick and bubbling, about 5 minutes. Remove from heat and whisk in garlic, lemon zest, and Parmesan until smooth. Season with salt and pepper. 
5. Pour bechamel over beans and mushrooms, then cover the roasting pan tightly with foil and bake until sauce is bubbling, 20 to 25 minutes. Uncover and bake until casserole is lightly browned on top, about 15 minutes longer. Let sit for 10 minutes before serving. 
6. Meanwhile, make the fried onions. In a medium bowl, toss onions in buttermilk, then let marinate for at least 10 minutes and up to 30 minutes. In a large bowl, whisk flour and cayenne with 1 tablespoon salt. 
7. In a HexClad 8 QT/7.5 L Hybrid Stock Pot, heat oil to 375°F/190°C, about 10 minutes. Use your hands to lift onions out of buttermilk and into flour mixture; discard excess buttermilk mixture. Toss onions in flour mixture to coat. Working in 3 batches, fry onions, stirring occasionally to separate, until golden-brown and crisp, about 3 minutes per batch. Transfer to a paper towel lined baking sheet to cool. 
8. Top casserole with fried onions to serve. 

MAKE AHEAD TIPS

The steamed haricots verts and cooked mushrooms can be refrigerated in an airtight container for up to 2 days. The fried onions can be made stored in an airtight container at room temperature for up to 2 days; to recrisp before serving, sprinkle over the top of the casserole for 10 minutes before it is done baking.