Preheat the oven to 200°C.
Peel the potatoes and the onion and cut into 5mm cubes. Cut the duck breast slices into 3mm strips.
Heat little olive oil in a frying pan and then add the diced potatoes. Colour the potatoes in the pan and then add the red onion and the butter. Cook for 4 minutes and then add the smoked duck slices. Cook for 2 minutes and then remove from the heat.
Place your tartlet mould upside down on the rolled out pastry. Cut around the mould to make a pastry disc. Repeat 6 times.
Spread the potato mixture between the 6 individual tartlet moulds and cover with a pastry round. Place all the moulds on a baking tray and cover with a sheet of baking parchment. Place another baking tray over the top and then transfer the tartlets to the oven and cook for 15 minutes. Remove the baking tray and cook for a final 5 minutes.
Turn the tartlets out on to dinner plates and serve with a green salad dressed with balsamic vinegar.
«This recipe can be adapted to make parcels rather than tarlets - place a little filling on a pastry round, cover with a second disc of pastry and then press the edges together, sealing with a little beaten egg.»