Place the oil into large frying pan and heat over a medium temperature
Add the onions and sauté until soft
Add the leek, herbs, fennel seeds and garlic and season to taste
Reduce the temperature and cook for 10 minutes
Remove from the heat and set aside
Pour the stock into a sauce pan and allow to heat gently over a low temperature
Preheat your oven to 170° Celsius
Butter an oven proof dish ** and arrange a layer of overlapping potato slices on the bottom
Then add a layer of the onion mix and season
Continue with the layers, ending with a layer of potatoes
Pour the warm stock over the potatoes so that they are just covered
Dot the top with a few small knobs of butter and place the dish/es onto a baking tray
Place into the oven and bake for 90 minutes
Remove from the oven and serve straight away
Notes
* if you cannot find this herb blend feel free to used mixed herbs. ** I used two small cocottes but you can use any dish you have that will fit the potatoes.