Sophie’s sardine puttanesca lasagne

Peel and finely dice your onion.Heat 2 tablespoons of olive oil and 2 tablespoons of the oil from your sardine tin in a saucepan over a medium heat. Add your onion and a pinch of salt and cook for about 20 minutes, or until it is soft and just starting to colour.Peel and finely chop your garlic, add it to the pan with your chilli flakes and cook it out for 2 minutes. Tip in your tomatoes, then mash them up with a spoon. Simmer on a low heat for 25 minutes.Preheat your oven to 190°C.While your red sauce simmers, make the white sauce. Melt your butter in a medium-sized saucepan over a medium heat. Once foaming, add your flour, mix to a paste and cook it out for 1 minute. Remove the pan from the heat and gradually pour in your milk in small increments, stirring all the while to ensure you have a smooth mixture before adding more.Once all the milk has been added, return the pan to heat, add your bay leaf, bring the mixture to a boil and then simmer for 3 minutes to thicken. Grate in 50g of your Grana Padano, tear in all your mozzarella and whisk to combine. Season to taste with salt and black pepper.Drain your sardines, squash, destone and roughly chop your olives and finely chop your parsley. Add your sardines and olives to the red sauce, then give it a mix and simmer for another 2 minutes. Season it up with the parsley, salt and pepper, to taste.Bring a saucepan of salted water up to a boil, then add your lasagne sheets one at a time. Cook for 3 minutes, or until they have gone floppy. Store them on greaseproof paper while you repeat with the rest.Spoon a little of your red sauce into the base of a 30 x 20cm baking dish. Arrange a layer of lasagne sheets neatly on top, tearing sheets where necessary to plug the gaps. Spoon over ⅕ of your remaining red sauce followed by ⅕ of your remaining white sauce, then more lasagne sheets. Continue like this until you are out of all your mixtures.Mix the top layer so the red and white sauces combine, pushing them all the way to the edges so the lasagne sheets are totally covered. Grate over the remaining Grana Padano, then bake for 40 to 45 minutes.Let your lasagne stand for 5 to 10 minutes before slicing it up and serving.Recipe © Sophie Wyburd