Preheat the oven to 400°F and line a baking sheet with parchment paper, set aside.

In a medium saucepan, combine the milk, butter, sugar, and salt and bring to a boil over medium heat.

Add the flour to the boiling mixture and stir vigorously with a wooden spoon until the paste starts to look dry and no longer clings to the pan or spoon. About 2 to 3 minutes, do not overmix.

Transfer the choux pastry dough to a large bowl or stand mixer and let it sit for 5 minutes. Stirring every couple of minutes to help it cool down.

Using a paddle attachment or hand mixer, beat in the eggs one at a time on medium-high speed until combined. Make sure the paste is completely smooth after mixing in each egg before adding the next. The choux pastry dough is ready when it sticks up without sagging on the end of a spoon.

Use choux pastry immediately or refrigerate for up to 4 hours (no longer).

Transfer the choux pastry dough to a pastry bag fitted with a Wilton 2A piping tip or similar and pipe onto the prepared baking sheet in mounds about 2-inches wide and 1-inch high, leaving about 2 inches of space between each one. Do not move the piping tip up as you pipe, just let the dough puff up around it. Sprinkle the mounds and the baking sheet with water, this helps the choux pastry dough to puff up while baking.

Bake on a lower rack for 10 minutes. REDUCE HEAT TO 350°F and bake for an additional 20 to 25 minutes until golden brown and firm to the touch.

Transfer to a wire rack and poke a hole in the side of each puff with a cake tester, toothpick, or paring knife to release heat and prevent the insides from getting soggy while they cool.

To make the filling, add heavy cream and vanilla to a chilled mixing bowl and beat with a hand mixer until bubbles form. Slowly add the sugar 1 tablespoon at a time and beat at medium-high speed until thick and creamy.

Add whipped cream to a piping bag fitted with a large tip of your choice.

Slice the cream puffs in half top and bottom and pipe the cream onto the bottom and then place the top back on the whipped cream. Dust with powdered sugar before serving.