• Preheat oven to 400-degrees F (205 degrees Celsius).

To make the profiteroles:

• Bring the water, butter, and salt to a simmer in a saucepan over medium heat.
• Add the flour and stir vigorously until the mixture comes together to form a dough. Allow it to cool slightly (approximately 10 minutes).
• Add the eggs, one at a time, beating extremely well with a wooden spoon after each addition. Continue until all four eggs have been incorporated, and the choux paste is smooth and glossy.
• Spoon (or pipe) 12 mounds of choux paste, evenly spaced, onto a baking sheet that has been lined with parchment paper or a silicone baking mat. 
• Tap down any dough spikes or points with a finger that has been dampened with water.
• Bake the profiteroles in a preheated oven for 30-35 minutes or until they're puffed and golden.
• Remove the profiteroles from the oven and immediately pierce each one with a paring knife or skewer to release any internal steam. 
• Allow them to cool completely on a wire rack.
• Using a serrated knife, gently cut the tops off each eclair, reserving the tops for later.
• Gently pull out any internal dough (if needed) so each puff is now a shell and ready to be filled. Set aside.

To make the orange curd whipped cream:

• Add the heavy cream to a very cold bowl that has been chilled for at least 20 minutes.
• Whip or whisk on high speed until the cream becomes thick and soft peaks form.
• Whisk in the confectioner's sugar and vanilla extract to combine.
• Gently fold in the orange curd and orange zest (optional) until completely combined.
• Spoon the orange curd whipped cream into the prepared profiterole shells, and gently set the reserved tops in place on each eclair.
• Sprinkle the cream puffs with additional confectioners sugar and chill until ready to serve.