2 pounds yukon gold potatoes, peeled and quartered
2 tbsp unsalted butter + more for greasing the dish
3/4 cup half and half
1 cup freshly grated gruyere cheese
1 tbsp fresh Italian parsley, finely chopped
5 egg whites + 1 egg
Kosher salt & freshly ground black pepper to taste
In a medium pot, add the quartered potatoes and fill the pot to just above the potatoes with cold water. Turn the heat to high and bring to a boil. Once boiling, lower the heat to medium (gentle boil) and allow them to cook about 15 minutes until easily pierced with a fork. Drain and return to the pot (off the heat).
Add in 2 tbsp of unsalted butter and mash the potatoes [see note]. Slowly add in the half and half while mixing until fully incorporated. Fold in the gruyere cheese and parsley. Once cheese is added, taste and add kosher salt/freshly ground black pepper to taste. Set aside.
Preheat oven to 350 degrees F.
In a medium bowl add the 5 egg whites and beat with an electric mixer until stiff peaks form.
Carefully fold the egg whites into the potatoes until incorporated, do not overmix.
In a 2 quart ramekin or 2 qt oven safe bowl, grease the entire inside with unsalted butter. Add the potato mixer to the bowl and smooth the top. In a small bowl, beat the 1 egg and using a brush, gently brush the entire top of the potato mixture.
Place in the oven and bake for 45 minutes or until the top is puffy and golden brown.
Serve immediately, soufflé will fall a bit with time.
For best mashed potatoes, use Yukon gold or russet potatoes
Bring your potatoes to a boil in a pot of cold water to ensure even cooking