Step by step

Drain the pasta and mix with the ingredients in the bowl

Tips
If you want to give more body to your macaroni sauce, you could add a teaspoon of cream to the butter and melt in a saucepan before transferring the mixture to the bowl with the anchovies and capers. And again, if you like the pairing of butter and anchovies, you could use it as a topping for bruschetta which you might serve as a finger-food hors d’oeuvre at a dinner party with friends.
Trivia
The combination of butter and anchovies is strongly rooted in the Roman culinary tradition, and is still served in many restaurants and osterias of the capital. A sandwich, pizza or plate of macaroni with butter and anchovies is the essence of Roman cuisine. A final note of interest: the combination of butter and anchovies was much loved and praised by the famous Roman poet Trilussa.