1.5lbsstarchy/floury potatoesYukon Gold (US) Maris Piper (UK)
375ml/1 ½ cupsdouble cream/heavy whipping creamno half and half
¼tspdried thyme or 3-4 sprigs fresh thyme (leaves only)
½tspgarlic powder
1tspsalt
120g/1 cupgrated extra mature cheddaror Gruyère cheese
85ml/1/4 cupdouble cream/heavy whipping creamfor the topping
60g/1/2 cupgrated extra mature cheddarfor the topping
Instructions
Peel and thinly slice the shallots. In a large pan, cook the shallots in olive oil over low heat, add a teaspoon of apple cider vinegar half way through. It will take 15-20 minutes for them to fully caramelise. Butter a 9X13 inch(3.5 Q or L capacity) baking dish and spread the caramelized shallots over the bottom. Preheat the oven to 450F/220C.
Peel the potatoes and slice them thinly either with a mandoline or in a food processor. Put them in cold water until needed.
Mix 375ml/1.5 cups double cream with the thyme, garlic powder, salt and 1 cup grated cheese, drain the potatoes slices and empty them into a large bowlm then coat them with the cream and cheese mix.
Arrange the potato slices in three or four rows in a prepared baking dish on top the shallots but instead of lying them down as usual, arrange them straight up like an accordion. Make sure the slices are not packed too tightly or they won't cook properly. Pour the remaining cream from the bowl all over, cover with foil and bake the preheated to 220C/450F oven for 50-60 minutes or until tender and easily pierced with a knife. (Spray the inside of the foil with cooking spray to prevent sticking to potatoes.)
Take out of the oven pour in ¼ cup of cream all over and ½ of the grated cheese, put back in the oven and broil (grill) for 7-10 minutes longer or until the potato slices look golden and crispy around the edges. Watch this stage carefully as ovens vary in temperature and the potatoes could be done sooner.