Melt 20g butter in a large pan over a medium heat and, once foaming, add the mustard powder and spices and toast for 30 seconds. Sprinkle in the flour and cook for 2 mins, stirring continuously. Slowly pour in the milk, stirring continuously until you have a smooth sauce. Bring to the boil, then reduce the heat to a simmer and bubble until slightly thickened.

Remove from the heat and stir in the cheddar and soured cream until the cheese has melted and everything is incorporated. Add the jalapeños and season well with salt and pepper. Cook the pasta following pack instructions, then drain well.

Meanwhile, melt the remaining 30g butter in a separate frying pan over a medium heat and, once foaming, cook the sweetcorn for 5-6 mins, stirring often until golden and charred. Pour most of the sweetcorn into the cheese sauce along with the cooked pasta and spring onions. Mix well and season to taste.

Heat the grill to high. Pour the pasta into a large baking dish and sprinkle over the mozzarella and remaining charred sweetcorn. Slide under the grill for 5-6 mins, or until golden and bubbling. Let stand for 10 mins, then serve.