Treacle ham and cheese pies

Method

1. Cook the cauliflower in a pan of boiling water, covered, for 4-6 mins, until starting to soften. Drain
2. Melt the butter in a saucepan over a medium heat
3. Add the onion and thyme, cover and cook for 10 mins, until softened
4. Remove the thyme, then add the flour, stir to combine, and cook for 2 mins more
5. Take off the heat and gradually add the milk, whisking constantly until you have a smooth sauce
6. Return to the heat and cook for 2-3 mins, continuing to whisk until it thickens
7. Remove from the heat and stir in the cheese and mustard, then the cauliflower and ham. Season, then set aside to cool
8. Preheat the oven to 190°C/fan 170°C/Gas 5
9. Grease 10 holes of a nonstick muffin tin
10. Roll out the pastry, on a flour-dusted surface, to the thickness of a £1 coin
11. Cut out 10 circles, 10cm across, then 10 more, 8cm across, with a pastry cutter
12. Put the big circles in the tin holes, pressing the pastry tightly into the corners
13. Spoon in the ham mixture, taking care not to overfill the pies
14. Brush the edges of the pastry with a little egg and top each one with a small circle
15. Press down around the edges to seal. Make a small air hole in the middle of each pie and brush with the remaining egg
16. Bake for 40 mins, until golden and crisp. Leave to stand for 5 mins, remove from the tin, then serve warm or cold with the extra mustard