Start by preheating your oven to 392°F (200°C). Next, in a medium saucepan, combine water, butter, and salt. Bring this mixture to a boil over medium heat.

Once bubbling, remove the pan from heat and add the flour all at once. Stir vigorously with a wooden spoon until the mixture forms a ball and pulls away from the sides of the pan. This should take about one to two minutes.

Transfer the dough to a mixing bowl. Let it cool for a few minutes, then add eggs one at a time, mixing well after each addition. Your dough should become smooth and glossy.

Using a piping bag or a spoon, scoop the dough into mounds, spacing them about an inch apart on a lined baking tray. Aim for 1.5 inches in diameter—these pastries will puff up!

Bake in your preheated oven for 20-25 minutes. The profiteroles should be golden brown and feel light. Make sure not to open the oven door during the first 15 minutes; you want those puffs to rise!

While the pastries bake, prepare the custard. In a saucepan, whisk together sugar, milk, and cornstarch. Over medium heat, bring this to a simmer while continuously stirring. Once it thickens, remove it from the heat and stir in egg yolks and vanilla. Return to the heat for a few minutes, then add butter. Let it cool completely.

Once the profiteroles are golden, take them out and let them cool on a wire rack.

After the pastries have cooled, use a small knife to make a tiny hole in the side. Pipe in your custard or filling of choice.

For an added touch, heat heavy cream and pour it over chopped chocolate to create a sauce. Drizzle over the filled profiteroles for that extra wow factor!