1 teaspoon salt for the cooking water plus more for the sauce
2 tablespoons unsalted butter
2 tablespoons flour
Dash black pepper
1 1/2 cups milk or half-and-half
1 to 2 tablespoons chopped fresh parsley or chives, optional
Instructions
Scrub the potatoes and cut any larger ones in half.
Put the potatoes in a medium saucepan with water to cover and 1 teaspoon of salt. Bring to a boil over high heat, cover the pan, and reduce the heat to medium-low. Cook for 15 to 20 minutes, until fork-tender.
Drain the potatoes, transfer them to a bowl, and keep warm.
Meanwhile, make the sauce. Heat the butter in a medium saucepan over medium heat.
When the sizzling subsides, add the flour, 1/4 teaspoon of salt, and a dash of pepper. Cook, stirring, for 2 minutes.
Gradually whisk in the milk or cream and continue cooking and stirring until thickened. Taste and adjust the seasonings.
Pour the sauce over the potatoes and add parsley if using. Stir gently to coat the potatoes and serve immediately.