Add your onions once the butter is foamy and stir frequently for 4-5 minutes
Turn the heat down to medium and continue to cook for about 25 more minutes
Onions should be sweet and cooked down significantly, but have not yet lost all of their integrity and begun to change color and caramelize
Add onions to the bottom of a 8 inch oven safe pan (cast iron works great here)
Preheat your oven to 350
Trim off the head and tali of your potatoes and slice each potato into 1/8th of an inch slices.
Mandolin very helpful here but not necessary if you have enough time
Was cut potatoes in cold water quickly to remove some but not all of the starch on them
Layer your potato slices in a circle around the outside of the pan on top of the onions
Season the potatoes “beautifully” with salt and pepper and then pour in chicken stock until it is halfway up the side of the potatoes.
Cut the remaining butter into small slices, and place on top of the potatoes around the pan. If you want additional add as much as your conscience allows.
Add a bay leaf or two between the two rings of potatoes
Place in an oven at 350 for 1 hour 30 minutes
If using a couple fresh sprigs of thyme, add them with 15 minutes left between the two rings of potatoes
If using dried or chopped, sprinkle them on top of the potatoes with 5 minutes left in the oven
Take out and enjoy! Potatoes should be fork tender and browned on top