Peel and slice the potatoes thinly, by hand or by using a mandoline or food processor.
Use a little of the butter to grease a dish around 30 x 20 x 5cm.
Arrange about a third of the potatoes in the bottom of the dish and pour over a third of the hot stock.
Sprinkle over half of the onions, herbs if using and season with salt and pepper.
Add the next third of potatoes and stock, the remaining onions, some herbs and seasoning.
Finish with the last of the potatoes, stock and seasoning.
Divide the butter into pieces and dot over the potatoes and bake for an hour at 200 C, 400 F, 180 FAN or Gas 6.
Notes
Disclaimer:The nutritional information provided is approximate and is calculated using online tools. Information can vary depending on various factors, but we have endeavoured to be as accurate as possible.Tip:There is no need to wash the potatoes after slicing. When the potatoes are cut they start to release the starch and this helps them to hold together in a dish.