Ingredients
Method
1.Preheat oven to 180ºC. Place an oven tray in to heat.
2.Carefully place the leek rounds in a pan with the butter and oil, then gently cook until they begin to soften and are cooked through – about 20-30 minutes. Turn once halfway through cooking but do so carefully as they like to unravel! Set aside to cool.
3.Line four 12cm tart tins (or one large 25cm) with the pastry and trim the edges neatly. Chill for 20 minutes.
4.In a bowl, whisk together the eggs, crème fraîche, cream, mustard and seasoning.
5.Sprinkle the grated Parmesan over the chilled pastry bases, then position the leeks, leaving a little space between each. Transfer the tarts to the oven tray to avoid spillage later. Pour the egg mixture around the leeks until each case is full. Top with scrunched up prosciutto and the extra cheese.
6.Gently slide back into the oven and cook for 20-25 minutes (30-35 minutes for a large tart) or until the pastry is golden and the filling just firm.
7.Leave to cool for 5-10 minutes before serving.
Note
- Prosciutto (and pancetta for that matter) can seem expensive but a little goes a long way in recipes such as this as the flavour is very intense. – Always remove tarts from fluted tins while still a little warm as they come away from the tin easier than when pastry is completely cold.