Tortelli with costmary

For the filling

• 1 kg chard
• salt and pepper
• ½ onion

Boil the chard in a little lightly salted water for around 10 minutes, turning 2–3 times so that it cooks evenly. Drain when still al dente and cool under cold running water. Squeeze out some of the excess liquid, leaving the leaves a little damp. Finely chop with a mezzaluna or chef’s knife.

Slice the onion and mince the costmary. Melt two spoonfuls of butter in a wide frying pan and s