40g smoked mushroom garum
200g button mushrooms, thinly sliced about 3mm
1kg Russet, Yukon Golden, or Maris Piper potatoes
3 handfuls of Parmigiano, grated
10g olive oil, divided
15g olive oil
2-3 sprigs of rosemary
For Fried Rosemary:
In a small saucepan, add the rosemary and olive oil and place over medium-low heat. The oil should form small bubbles but should not boil. Maintain a low heat to prevent the olive oil from burning. Lightly fry the rosemary for 5-10 minutes. Use a slotted spoon to pick out the rosemary and let dry on a paper towel. Reserve oil.
For Dauphinoise Potatoes:
Preheat oven to 145ºC.
Wash and finely slice the potatoes using a mandoline. Set aside in cold water until required.
In a mixing bowl, combine sliced mushrooms and the smoked mushroom garum - use your hands to lightly massage the mushrooms and evenly coat in the garum. Marinate for 5 minutes, toss again, and marinate for another 5 minutes.
In a small bowl, combine the mascarpone, cream, and 1 handful of grated Parmigiano. Evenly spread the mixture on the bottom of a small baking dish.
Strain the potatoes. Shingle the first layer of potatoes over the mixture. Cover the first layer of potatoes with half of the marinated mushrooms, 5g of olive oil, and a thin layer of Parmigiano. Repeat this one more time using the second half of the mushrooms. Arrange the top layer of potatoes. Drizzle the remaining garum, 5g olive oil, Parmigiano, fried rosemary, and the remaining oil from frying the rosemary.
Cover the baking tray with a lid or parchment paper and bake for 40 minutes. Remove the lid and turn heat up to 210ºC and bake for another 20 minutes to form a golden crust.
Let cool for at least 15 minutes before serving. Serve with a fresh salad, or as a side with any protein or a fried egg.