Clean and wash the spinach, cook it in a covered pan with the oil, over a low heat, for about 10 minutes. Stir from time to time and add just a little salt. Squeeze out the spinach and chop it, on a board, with a knife. Put the chopped spinach in a bowl, add the eggs, grated pecorino, nutmeg, some salt and pepper, and stir. Finely chop the pine nuts and add them to the mixture, together with a spoonful of milk to soften it. Stir again to mix everything together. Prepare 4 individual ramekins: grease the inside with a little softened butter and sprinkle with breadcrumbs, this will make it easier to get the flans out when cooked. Fill the ramekins with the mixture up to 1 cm from the top, arrange them in a baking tray and pour in water to ⅔ up the ramekins, so that they cook in a bain-marie. Bake in a preheated oven, at 180 °C, for 25-30 minutes. When this time is up, try sticking a toothpick into the centre of a flan: it should come out dry. Once they have cooled down a little, you can tip them out with the help of the blade of a knife. For the cream of pecorino: heat the milk in a small, deep saucepan (it mustn’t boil). Melt the butter in a heavy-bottomed pan over a low heart, then sprinkle in the flour, sifted through a sieve. Stir with a whisk until you obtain a dense, smooth, golden-coloured cream. Add the milk you heated previously, a little at a time, and stir well with the whisk. Cook over a low heat, stirring continuously. When the mixture has thickened, take the pan off the stove and gradually add the pecorino grated coarsely (using a grater with larger holes), stirring with a hand whisk. The cream should be fairly dense: if you scoop some out with a spoon and then let it fall back into the pan, it should remain on the surface for a few moments before sinking. Pour a good spoonful of the cream of pecorino on top of each flan and serve.