Pesto alla Genovese

1. Combine basil, garlic, parsley, and salt in a food processor pulse to barely mince Add the pine nuts and pulse to coarsely chop Add the grated cheese With maching running, add the oil in a thin-steady stream process until thickened Add the butter and process until smooth Thin with hot water as necessary Cover and chill for up to 48 hours or freeze to store.
2. Serve at room temperature.