Green Bean Casserole from Scratch

Method

1. 1

   Heat the oven

   Heat the oven to 200°C (180°C fan). Butter a baking dish about 20 x 30 cm (2 litres).

2. 2

   Blanch the beans

   Bring a large pan of water to the boil over high heat and add 1 tbsp salt. Boil the beans for 4 to 5 minutes, until bright green and just tender with a little bite.

3. 3

   Cool the beans

   Drain, then rinse under cold running water until cold, so they stay green. Drain well and pat dry.

4. 4

   Brown the mushrooms

   Melt the butter in a large frying pan over medium-high heat. Cook the mushrooms for about 8 minutes, stirring now and then, until their liquid has gone and they're browned.

5. 5

   Add the aromatics

   Lower the heat to medium, add the onion and cook for 5 minutes, until soft. Stir in the garlic and thyme for 30 seconds, until fragrant.

6. 6

   Cook the flour

   Sprinkle over the flour and stir for 1 minute, until no dry patches remain.

7. 7

   Make the sauce

   Pour in the milk a splash at a time, stirring all the time, then add the stock and cream. Simmer for 3 to 5 minutes, stirring, until thick enough to coat a spoon.

8. 8

   Season

   Stir in the nutmeg, pepper and 1/2 tsp salt, then taste. The fried onions are salty, so only add more if it tastes flat.

9. 9

   Combine

   Take the pan off the heat and fold in the beans and a third of the fried onions. Spread evenly in the dish.

10. 10

    Bake

    Bake for 20 minutes, until bubbling around the edges.

11. 11

    Add the topping

    Scatter over the rest of the fried onions and bake for 5 minutes more, until deep golden. Keep an eye on them, as they catch quickly.

12. 12

    Rest

    Leave to stand for 5 minutes so the sauce settles, then serve hot.

Tips

• Make it up to the end of step 9 a day ahead, cool, cover and chill. Bake for 30 minutes, then add the topping.
• Pat the beans properly dry, or the sauce will turn watery in the oven.
• Look for crispy fried onions near the salad toppings in the supermarket.

Swaps

• Use chicken stock instead of vegetable stock for a richer sauce.
• Frozen green beans work too; skip the blanching and just thaw and pat them dry.
• Button mushrooms can replace the chestnut mushrooms, with a slightly milder flavour.

Storing

Refrigerate leftovers covered for up to 3 days, and reheat in the oven until hot all the way through.