1 cup water
1 stick (1/2 cup) unsalted butter
1/4 teaspoon salt
1 cup all-purpose flour
3 large eggs
1 or 2 eggs, if needed
2 tablespoons milk
In a heavy saucepan, bring to a boil 1 cup water with 1 stick (1/2 cup) unsalted butter, cut into pieces and 1/4 teaspoon salt over high heat. Reduce the heat to moderate, add 1 cup all-purpose flour all at once. Beat mixture with a wooden paddle until it leaves the sides of the pan and forms a ball. Transfer the mixture to a bowl and with an electric mixer at high-speed beat in 3 large eggs, one at a time; beating well after each addition. The batter should be stiff enough to hold a soft peak.
If it is too stiff, break 1 or 2 eggs in a bowl and beat them lightly and add enough to the batter to thin it to a proper consistency.
Put in a pastry bag fitted with a 1/2 in plain tip and pipe out mounds about 1 each in diameter and 1 inch apart on a lightly buttered baking sheet. Brush tops with an egg wash made from 1 egg and 2 tablespoons milk beaten together.
Bake the puffs in the middle of a preheated hot oven (425-degrees) for 12 minutes, reduce heat to 375-degrees and bake 12 minutes more. Cut off and discard tops, scoop out the doughy center and place each in the oven. Turn off the oven and leave puffs in for 10 minutes. Take from oven and cool on a rack.