This is my new favourite dish because it is very straightforward and tastes amazing.
- Roll out the pastry and line a greased 23cm pie dish.
- Put some baking paper over the base and fill with dry beans, or similar
- Bake blind in a 200 degC oven for 15 minutes.
- Take the beans out, prick the base and cook for a further 5 minutes.
- While you are baking the crust, boil the potatoes until just cooked.
- In a frying pan, melt the butter and cook the onions, garlic and thyme on a very low heat.
- If you do this for at least 15 minutes, they will soften and caramelise, which will deliver a lovely flavour.
- When the potatoes are cooked, dice, then add to the onion mixture along with the cream, cheese, mustard and salt and pepper.
- Pour into the pastry crust and bake for 15 minutes until golden brown.