Easy Jerusalem Artichoke Soufflé

Preheat the oven to 390°F. Butter 4 soufflé dishes or ramekins well.
Peel and dice the Jerusalem artichokes into ½ x ½ inch size (1 x 1 cm).
14 oz. Jerusalem artichokes
Melt butter in a skillet. Add the water and diced artichokes and simmer over medium heat until the water evaporates and the artichokes are tender. Add a splash more water if needed.
2 tablespoons butter, ⅓ cup water
Brown briefly, then mash with a fork.
In a separate pan, melt the remaining butter.
2 tablespoons butter
Add the flour all at once and stir for 2 minutes without browning.
2 tablespoons all-purpose flour
Whisk in the cold milk in one go until smooth and thickened. Remove from heat.
⅔ cup whole milk
Stir in the mashed artichokes, egg yolks, cheese, salt, pepper, and nutmeg.
4 egg yolks, ½ cup Parmesan cheese, ¼ teaspoon salt, ⅛ teaspoon ground black pepper, ⅛ teaspoon ground nutmeg
In a very clean bowl, beat the egg whites with a pinch of salt until stiff.
4 egg whites, ⅛ teaspoon salt
Fold one-quarter into the artichoke mixture to loosen it, then gently fold in the rest.
Spoon into the prepared dishes and bake for 20 minutes without opening the oven. Serve immediately.