Spiced Harissa Lamb Pasties with Sweet Potato

Heat the vegetable oil in a large pan over medium-low heat. Add the finely chopped onion and leek, stirring occasionally for 10-15 minutes until they are soft and translucent.

Push the vegetables to one side of the pan and increase the heat to medium. Add the lamb mince and fry for 10-15 minutes, breaking it up with a wooden spoon, until the liquid has evaporated and the meat is browned. Meanwhile, prep the preserved lemon by removing the pith and finely chopping the peel.

Stir in the lemon peel, crushed garlic, diced sweet potato, cumin, harissa, and tomato purée. Cook for 1-2 minutes until fragrant. Pour in 200ml of water, scraping up any browned bits from the bottom. Partially cover with a lid and simmer for 10 minutes until the sweet potatoes are just tender and the mixture is relatively dry. Remove from heat and allow to cool completely.

To make the pastry, combine the butter, lard, flour, and 2 tsp of salt in a food processor. Pulse until the mixture looks like fine breadcrumbs. With the motor running, slowly add 6 tbsp of cold water, pulsing until the dough clumps together. If it's too dry, add 1-2 more tbsp of water. Tip onto a surface, knead briefly to smooth, shape into a disc, wrap in plastic, and chill for 30 minutes.