These rich and delicious individual tarts are very filling – each is perfect with salad for lunch. There are two flavours – one for salmon-lovers, and another that is just right for veggies.
Heat the oven to 200°C/180°C fan/Gas 6.
Make the pastry. Place the flour, salt, butter and shortening in a food processor and pulse until it forms fine crumbs. Add the eggs and 1 tablespoon of cold water, then blitz until you have a clumpy dough. Turn out the dough onto the work surface and bring it together into a ball, adding another 1 tablespoon of water, if needed. Roll into a disc, cover and chill for 30 minutes.
Lightly dust a work surface with flour, cut the dough into 8 equal pieces and roll each to a circle about 16cm in diameter. Drape the pastry inside the tart tins, press against the sides to neatly line each tin. Trim the edges. Prick the bases with a fork, place the tart tins on a large baking tray and chill for 30 minutes.
Line each chilled pastry case with a square of foil or baking paper and fill with baking beans. Bake for 15 minutes, until the pastry is golden at the edges. Reduce the oven temperature to 180°C/160°C fan/Gas 4, remove the baking beans and foil or baking paper and return the pastry cases to the oven for a further 5 minutes to dry out the bases.
Make the custard. Melt the butter in a small frying pan, add the shallots and fry over a medium heat for 5 minutes, until softened but not coloured. Spoon the shallots into a bowl and leave to cool. (Do not wash the pan as you’ll need it again.)
Add the mustard, stock cube, double cream and eggs to the shallots, season well and whisk to combine. Cover and set aside until needed.
Prepare the leeks for the leek and salmon filling. Melt the butter in the frying pan over a low–medium heat. Add the leeks and fry for 5 minutes, until softened. Season well, remove from the pan and allow to cool.
Make the spinach and mushroom filling. Melt the butter in the frying pan over a medium heat. Add the mushrooms and cook for 3–4 minutes, until soft. Add the spinach, stir to combine and cook for 1–2 minutes, until the spinach is wilted and tender. Season well and leave to cool slightly.
Divide the diced salmon and cooked leeks equally between 4 of the pastry cases. Divide the spinach and mushroom filling equally between the other 4 tart cases. Scatter all the tarts with the grated cheese and slowly pour the custard mixture into each quiche to fill.
Bake the quiches for about 25 minutes, until just set in the middle and golden on top. Serve at room temperature.