Cook the macaroni in a pan of boiling salted water for 6-7 mins until almost cooked through. Drain and set aside in a bowl.

Heat 1 tbsp oil in a large pan over a medium-low heat and fry the onion for 8-10 mins until softened but not golden. Stir in the garlic and cook for a further minute, then turn up the heat to medium and fry the thick pork sausages, pushing them down to break apart. Cook for 6-8 mins until cooked through and beginning to brown, then stir in the sliced sprouts and a good pinch each of salt and pepper. Cook for 5-6 mins more until the sprouts have softened and the sausages are cooked through. Remove the sausages and sprouts to the bowl of pasta.

Heat the oven to 200C/180C fan/gas 6. Wipe the pan clean and melt the butter over a medium-low heat. Stir in the flour until combined, then cook for 1 min before mixing in a big splash of the milk. Stir the rest of the milk in gradually and, once it’s all incorporated, bring to a simmer (whisk until smooth if it still has lumps) and cook for another minute. Remove from the heat and stir in all the cheddar and half the parmesan. Mix the cheese sauce, sausages, sprouts and pasta together, then tip into a large ovenproof dish.

Combine the remaining parmesan and the breadcrumbs, then scatter this over the pasta mixture. Bake for 30-40 mins until golden on top.