Cheese and Onion Pie

This staple homemade vegetarian pie combines cheese, potato, cream and shortcrust pastry and provides comfort food of the highest order! Best eaten on a chilly afternoon in front of a roaring fire. We suggest using a food processor for ease and to speed things up but you can make the pastry by hand if you prefer. Both methods yield delicious results. We'd also recommend using white floury potatoes. Cut the potatoes into slices, approximately 3-5mm thick, but there's no need to be super precise.

Ingredients

For the pastry:

400g plain flour

100g vegetable fat (I used Trex), roughly chopped

100g salted butter, roughly chopped

½ tsp salt

150ml cold water

For the pie filling:

medium onion, chopped

knob butter

large clove garlic, crushed and chopped

300g raw potato, peeled and sliced

2 tsp mustard powder

1 heaped tbs plain flour

½ tsp vegetable stock powder (optional)

200 ml semi-skimmed milk

50ml double cream (plus extra for painting on top of the pie)

100g mature cheddar cheese, grated

25g parmesan cheese, grated

Equipment

large saucepan with a lid

rolling pin

Tala Performance pie dish

kitchen scissors

kitchen foil

Tala pie beans

measuring spoons

wooden spoon

pastry brush

small sharp knife

pastry cutters (we used the wide end of a large piping nozzle and a circular pastry cutter)

cocktail stick

1. Blitz the flour, vegetable fat, butter and salt in a food processor until the mixture has the texture of sand. Add the water and pulse until the dough just starts to clump together.
2. Gather the dough into a ball and cut into two pieces, one slightly bigger than the other. Place both pieces in the fridge to chill while you work on the filling.
3. Preheat the oven to 170 degrees Celsius (338 degrees Fahrenheit). Sprinkle the work surface with flour and then roll out the larger portion of dough to a rough circle with a thickness of about 3mm. You'll need a pastry circle big enough to cover the bottom and walls of the pie dish.
4. Lift the pastry circle into the pie dish, gently push into position and use the kitchen scissors to trim all the way round the edge of the dish (you do not need to trim right up to the edge as the pastry might shrink a bit in the oven). Place the  dish in the fridge until the oven comes up to temperature.
5. Place a large piece of foil over the pastry (large enough to hold the baking beans), tip in the baking beans and bake for 25 minutes. Gather the foil at the top and carefully lift out the foil package containing the baking beans and set them aside to cool. Place the pie dish back in the oven for the pastry to crisp up – five minutes will do the trick. Bring the pie dish out of the oven and allow to cool until needed. (It does not need to cool completely.)
6. While the pastry is baking, melt a large knob of butter in a large saucepan and fry the chopped onion (the onion needs sweat, but don't let it caramelise) for about five minutes, then add the garlic and fry gently for a further two minutes. Add the mustard powder, flour and stock powder (if using it) and stir so that the vegetables are completely covered.
7. Add the milk and cream, the vegetables should be just about covered with liquid, and simmer on a very low heat for about ten minutes. Stir now and then with a wooden spoon to stop the mixture sticking to the bottom of the pan. Cover the pan when not stirring.
8. Turn off the heat, then stir in the grated cheeses and season generously with freshly ground black pepper and salt.
9. Transfer the potato mixture to the pie dish and level it roughly with the back of the wooden spoon.
10. Return to the remaining pastry and roll it out again to make a circle big enough to cover the pie completely. Use a pastry brush to paint the baked pastry edge of the pie with double cream to act as a glue, then lift the pastry circle over the pie to make a lid and press it down around the sides.
11. Use a small sharp knife to cut three steam holes in the top of the pie.
12. Gather the remaining pastry scraps and roll out again, this time quite thinly, to make some decorations to stick on top. I chose a large nozzle tip to cut small circles to go around the sides ('potatoes', which I 'speckled' by poking little holes with a cocktail stick) and I made wedges of 'cheese' by using a larger circular cutter to make circles which I cut into wedge shapes with a sharp knife.
13. Paint the entire surface of the pie with double cream, then attach the decorative pieces of pastry and brush these on top with a little cream as well.
14. Bake for 60 minutes at the same temperature until the pie is golden brown. Allow the pie to rest for about 20 minutes before serving.