These shortbread are great served with Sticky Melon Jelly with Amaretti, with poached stone fruit and mascarpone, or with a hard cheese such as pecorino sardo or a good cheddar.
Preheat oven to 170°C/340°F/Gas Mark 3–4. Line two baking trays with baking paper. Place butter and sugar in a food processor and blitz for 20 seconds. Scrape down the bowl, add remaining ingredients and blitz for 10 seconds. Tip into a bowl and gently bring together. Divide in half, t