Heat the oil in a large pan and gently fry the spring onions and garlic for 2 minutes, without allowing the garlic to brown.
Drain the pilchards, then rinse gently in cold water to wash off most of the chilli sauce. Add the drained pilchards and 500ml water to the pan.
In a separate small bowl, mix the contents of the sachet of KNORR Thick White Onion Soup with 125ml water to form a smooth paste, then stir this gently into the pan.
Simmer for 5 minutes, stirring occasionally, until thick.
Add the spinach leaves and simmer over a low heat for another 7-10 minutes, or until the spinach is just cooked.
Stir in the cream and season to taste with salt and black pepper.
To make the topping, place the bread slices in a blender and whizz to create breadcrumbs. Heat a little oil in a separate pan and gently fry the crumbs until golden and toasty. Let the crumbs cool for a minute, then stir in the fresh parsley and lemon zest.
Bring a large pot of salted water to the boil and cook the pasta according to the instructions on the packet.
Combine the sauce with the cooked, drained pasta and transfer to a serving dish. Scatter with the breadcrumb mixture and serve immediately.