From BBC Good Food
- 50g butter
- 2 tsp mustard powder
- 600ml milk
- 200g mature cheddar , grated
- 2 large potatoes , sliced into rounds
- 1 head broccoli , cut into little florets
- 200g frozen peas
- small bunch chives , snipped
- 50g flour
- 1 head cauliflower , cut into little florets
- Heat oven to 220C/fan 200C/gas 7
- Put the kettle on
- Melt the butter in a saucepan, then stir in the flour and mustard powder and cook for 1 min. Gradually stir in the milk until smooth with no lumps, then keep stirring until the mixture begins to bubble and thickens to a creamy sauce. Remove from the heat, then stir in all but a handful of the grated cheese.
- Put the hot water from the kettle into a large pan & bring to the boil. Cook the potato slices for 5 mins, tip in the broccoli and cauliflower for another 3 mins, then finally add the peas for 1 more min.
- Drain all the veg and pat dry.
- Reserve enough potato slices to cover the top of the finished dish, then gently stir the rest of the vegetables into the sauce with the chives.
- Tip into a deep ovenproof dish, arrange over the reserved potato slices, then sprinkle with remaining cheddar.
- Bake for 20-25 mins until the topping is golden and crisp, then serve straight from the dish.