Preheat the oven to 400° F.

Butter and flour 8 -6-ounce ramekins.

In a medium saucepan cover the potatoes with cold water and season with salt. Bring to a boil and then immediately reduce to a simmer. Cook the potatoes for 20 minutes or until tender. Return the potatoes to the pan and cook over medium-high heat for 2 -3 minutes or just until they are dried out. Press the potatoes through a potato ricer into a large mixing bowl. Add 2 tablespoons of butter, the half and half, gruyère cheese, herbs and salt and pepper and mix well. Fold in the egg yolks.

In the bowl of a standing mixer, beat the 7 egg whites until foamy. Add the cream of tartar and continue to whip the whites until stiff peaks form. Using a rubber spatula, fold the egg whites into the potato mixture. Spoon the mixture into the prepared ramekins and bake in the bottom third of the oven for about 25 minutes or until the soufflé has puffed and is golden brown.

Serve immediately.