Place the butter in a frypan on a medium heat. Saute the onions and garlic until translucent.
When the onion and garlic are cooked, add the arrowroot powder and cook for another 2 minutes
Add the vegetable stock to the fry pan along with the mixed vegetables. Reduce the temperature to low and allow to simmer until the veggies have softened and the sauce has thickened.
Once the sauce has thickened, add the cream and then season with salt and pepper. Allow to simmer for another 5 minutes.
When pie bases are cooked through, remove from the oven and spoon in a generous helping of the pie filling.
Finally divide your smaller ball of dough into six portions, flatten into circles and place on top, firmly pushing the edges to join the lower pie shell.
Prick the top with a fork and return to the hot oven until pies are golden brown.