Heat the oven to 200C/180C fan/gas 6. Combine the breadcrumbs, parsley and 25g parmesan, then set aside. Heat the oil and butter in a large flameproof casserole over a medium heat and fry the onion for 5 mins until starting to soften. Stir in the garlic, and cook for 1-2 mins more to soften slightly, then stir in the cream, milk and remaining parmesan. Bring to a simmer and cook until the cheese has melted, then season well, stir and remove from the heat.

Tip in the asparagus and ensure it is submerged in the sauce. Nestle in the salmon fillets, skin-side down. Scatter the cheesy breadcrumb mixture over the salmon fillets, then transfer to the oven and bake for 14-16 mins until the salmon is cooked through and the breadcrumb topping is lightly golden.