This is the simplest of all the cream sauces and is a speciality from the Emilia-Romagna area of Italy, which is centred on Bologna.

Put a pan of salted water on to boil, then take a small sauce-pan and melt 1.5 ounces of butter in it. For 250 grammes of tortellini add to the melted butter a quarter pint of cream and let it boil. Reducing cream has the effect of thickening it and changing its colour from white to a golden straw colour.

While this is happening keep an eye on your pasta water. When it is boiling vigorously add the tortellini and stir to prevent sticking. Between 12 and 14 minutes is usually enough for tortellini, but check the packet which should give a recommended cooking time.

When the cream has assumed the colour and consistency that you want, turn the heat right down to very low and grate some parmesan into it. About 2 ounces should be readily absorbed by the cream. Stir until the parmesan is incorporated.

Drain the tortellini when cooked, return them to the pot and pour on the sauce. Stir and serve with a sprinkle of parmesan on top.