4 blanched and refreshed large Savoy cabbage leaves, the rest of the cabbage reserved
1 free-range egg, beaten, to glaze
salt and freshly ground black pepper
For the watercress purée
75g/2½oz unsalted butter
50ml/2fl oz–100ml/3½fl oz double cream
handful watercress leaves, plus extra sprigs to garnish
For the pigeon legs, pour the stock into a large saucepan and add the legs to the pan. Add the vinegar, thyme, bay leaf, garlic and celery and braise slowly for 60–90 minutes. Remove the legs from the pan and leave to cool and drain on a plate.
Meanwhile, for the pie, season the pigeon breasts with salt and pepper and sear in a hot frying pan. Set aside. Heat the oil in a separate frying pan and sauté the shallots, garlic, porcini mushrooms and tarragon until soft. Add the Madeira and cook until reduced. Add the stock and cook until reduced by half. Stir in the livers. Season with salt and pepper and set aside to cool.
Preheat the oven to 210C/190C Fan/Gas 6.
Roll out the pastry into two small rectangles. Lay the cabbage leaves on one of the pastry rectangles, top with the mushroom mixture and then the cooked pigeon breasts. Top with the remaining mushroom mixture and place another layer of cabbage on top. Lay the remaining pastry on top and seal around the edge using a fork. Slash the top of the pastry and place on a line pastry tray. Brush with the beaten egg and bake for 25–30 minutes, or until golden on top and cooked through.
To make the purée, melt the butter in a sauté pan, add the cabbage and watercress and cook until wilted. Finish with the cream and salt and pepper. Blitz with the cream to a smooth purée.
Divide the purée between warmed plates, cut the pie in quarters and garnish with the pigeon legs and watercress sprigs. Serve immediately.