Cauliflower, Leek and Cheddar Pie with Mustard and Thyme Pastry

• plain flour↗500g g

  plus extra for dusting

• cold butter↗250g g

  cut into cubes

• English mustard↗1½ tbsp tbsp
• thyme leaves↗1 tbsp tbsp
• egg↗1

  beaten for glaze

• cauliflower↗1 small to medium
• olive oil↗1 tbsp tbsp
• leek↗2 medium

  sliced

• eggs↗2
• English mustard↗1 tsp tsp
• mature cheddar↗400g g

  grated

Step-by-step instructions

1. 1

   For the pastry, place the flour in a food processor together with the butter, mustard and thyme leaves and pulse until the mixture resembles crumbs. Add 4–6 tbsp cold water and pulse again until a ball forms. Wrap and chill for 30 minutes.

2. 2

   For the filling, break the cauliflower into bite‑size florets (reserve the leaves for broth or roast them until crisp and serve alongside the pie), and cut the stems into 2 cm pieces. Steam in a steamer or a steaming basket over a pot of boiling water for 8–10 minutes, until the stem pieces are tender but not fully cooked. Remove from the steamer, let cool and dry on a plate.

3. 3

   Heat the oil in a pan over low heat and sauté the leeks with a pinch of salt for 10 minutes, until they become soft. If the leeks start to lightly brown, add a little water and cook until the water evaporates. Remove from heat.

4. 4

   Cut off one third of the pastry and set aside. Roll out the remaining dough on a flour‑dusted surface into a circle large enough to line a 25 cm diameter, 7 cm deep pie tin (enameled tins work). Line the tin and set aside.

5. 5

   Beat the eggs in a large bowl with a little seasoning. Set aside a small portion of the beaten egg in a small bowl, then gently fold the cheese, cauliflower and leeks into the remaining egg mixture. Spoon the filling into the pie tin and spread evenly. Roll out the remaining pastry and cover the pie, using the reserved egg to seal the edges. Pinch the edge and trim excess, then chill for 20 minutes.

6. 6

   Preheat the oven to 200 °C/180 °C with convection/gas 6. Brush the top of the pie with the remaining beaten egg and bake for 45 minutes, until golden and crisp. Let stand for 10 minutes before serving with roasted potatoes.