Preheat oven to 425°F (220°C). Line two baking sheets with parchment paper and set aside.

In a medium saucepan, combine water, butter, and salt. Bring to a rolling boil over medium-high heat, ensuring the butter is fully melted.

Remove from heat and immediately add all the flour at once. Stir vigorously with a wooden spoon until a smooth ball forms and pulls away from the sides of the pan, about 1 minute.

Transfer the dough to a mixing bowl and let cool for 3-4 minutes, stirring occasionally. Add eggs one at a time, beating well after each addition until the dough is smooth, glossy, and slowly drops from the spoon in a V-shape.

Transfer dough to a piping bag fitted with a 1/2-inch round tip. Pipe 1 1/2-inch mounds onto prepared baking sheets, spacing them 2 inches apart. Lightly flatten any peaks with a dampened finger.

Bake at 425°F for 15 minutes without opening the oven door. Reduce heat to 350°F (175°C) and bake for another 15-18 minutes until deep golden brown and firm to the touch. Turn off oven, poke a small hole in the bottom of each puff with a skewer, and leave them in the turned-off oven for 10 minutes to dry out.

While puffs cool completely, make the lemon cream. In a large bowl, beat the heavy cream, powdered sugar, and vanilla extract with an electric mixer on high speed until stiff peaks form, about 3-4 minutes.

In a separate bowl, whisk the lemon curd until smooth. Fold one-third of the whipped cream into the curd to lighten it, then gently fold in the remaining whipped cream and lemonzest until just combined.

Cut each cooled puff in half horizontally or pipe filling through the bottom hole. Generously fill each puff with lemon cream using a piping bag or spoon. Dust with powdered sugar just before serving.