For the crust: 2 cups all-purpose flour, plus extra for dusting
1/2 tsp kosher salt
1/2 cup unsalted butter, chilled and cubed
1/4 cup shortening, chilled and cubed
4 - 5 tbsp iced water
For the filling: 3 large eggs
2 large egg yolks
1 1/3 cups half-and-half
2/3 cup milk
1 pinch kosher salt
1 pinch grated nutmeg
1 cup Gruyere, or Swiss, grated
1 small bunch chives, roughly chopped
2 tbsp parsley, chopped
freshly ground black pepper
For the crust: Combine the flour, salt, butter and shortening in a food processor and pulse a few times until the mixture resembles rough breadcrumbs.
Add 2-3 tablespoons of the water and pulse until a dough forms around the blade of the processor, adding more water as needed by the tablespoon. Mix in a little more flour if the dough is too sticky.
Once the dough has come together, turn it out from the processor and shape into a disc. Wrap in plastic wrap and chill for at least 30 minutes.
After chilling, preheat the oven to 170°C (150° fan) | 325F | gas 3.
Roll out the chilled dough on a lightly floured surface to 0.25" thickness. Cut out four rounds and use them to line the base and sides of four individual fluted molds. Trim away any excess overhanging pastry and prick the bases all over with a fork. Chill until needed.
For the filling: Whisk together the eggs, egg yolks, half-and-half, milk, salt, nutmeg, grated cheese and most of the chopped chives in a large mixing bowl or jug.
Divide the egg custard mixture between the lined pastry cases. Place the molds on a large baking sheet and top with the remaining chives and the parsley.
Bake for about 45-50 minutes until the crusts are golden-brown and the fillings are set with a slight wobble when poked.
Remove from the oven to a cooling rack. Serve warm or at room temperature.