Whipped mashed potatoes

Ingredients:

• 1.8 kg Yukon Gold potatoes, washed
• 4 liters of whole milk
• 110 g melted unsalted butter
• 1 tbsp coarse salt

Preparation:

1. Peel the potatoes and slice them as thinly as possible with a mandoline, placing them directly into a large 8-quart container filled with 4 liters of cold water. Cover and refrigerate overnight.
2. Drain the potatoes and rinse with fresh cold water; dry them in a salad spinner. Transfer the potatoes to a 11-quart (11-liter) saucepan, cover with milk, and place over medium heat. Bring to a boil, about 35 minutes. Reduce the heat to maintain a gentle simmer and cook, uncovered, until the potatoes are tender and begin to fall apart, 25–30 minutes.
3. Pour off 1 cup of the milk the potatoes were boiled in. Drain the potatoes in a colander and return them to the pan. Mash the potatoes until they form a puree. Add the reserved hot milk, butter, and salt and beat with a mixer on low speed for 15–30 seconds. Be careful not to overmix the potatoes.