Tarragon, the gorgeously named “dragoncello”, is actually little used in Italy, despite the country’s immoderate passion for all things anise. You find tarragon used only here and there, mainly in Tuscany; indeed, it is sometimes referred to as erba di Siena, the herb of Siena. Its chief appearance in those parts is in the salsa al dragoncello, where the herb is pounded with breadcrumbs and garlic and then emulsified with olive oil to produce a fragrant sauce customarily served with plain boiled meats. To be honest, I’m not sure I had that in mind when I first made this: all I wanted was to create a version of that fabulously spiky Italian green sauce, tweaked to suit chicken, which for me (and I hope this display of frankly French influence is forgiven in Italy) means tarragon. For US cup measures, use the toggle at the top of the ingredients list.