Rich and Creamy Mixed Mushroom Pie with Thyme Pastry

In the same pan, melt the remaining butter over low heat. Sauté the sliced onion with a pinch of salt for 10-15 minutes until soft and caramelized. Stir in the remaining flour and cook for 2 minutes. Deglaze the pan with white wine vinegar and brandy, simmering until the liquid is nearly gone.

Gradually stir in the stock and bring to a simmer. Add the Marmite, double cream, and black pepper. Fold in all the fried mushrooms and the drained rehydrated mushrooms. Transfer the mixture to a bowl and let it cool completely before folding in the chopped tarragon. This filling can be made up to two days in advance.

Preheat your oven to 200°C (180°C fan/gas 6). Spoon the cold filling into a 28cm ceramic pie dish. Roll the pastry out to a 1cm thickness. Cut thin strips from the edge and press them onto the rim of the dish. Drape the remaining pastry over the top, crimp the edges to seal, and trim the excess. Brush with an egg wash (remaining egg beaten with a splash of milk), score the top lightly, and decorate with pastry scraps if desired. Chill for 30 minutes, then apply a final coat of egg wash.

Bake for 40-45 minutes until the pastry is crisp and dark golden. Allow the pie to rest for 15 minutes before serving. Pair with mashed potatoes and seasonal green vegetables.