Make the Caramel: Melt the Sugar in a pot over medium heat. Stir in the water and allow to caramelize, stirring continuously. Let the This forms a syrup. Allow the syrup to brown into a caramel. When it reaches a nice color, stir in the butter and salt. You want it to be relatively stiff. Set aside for later.
make the Pastry Cream: Heat the cream and half the sugar in a heavy pot over medium heat, whisk until well blended. In a separate bowl, Whisk the egg yolks and eggs with the remaining sugar, cornstarch, vanilla, and lemon zest. Then ladle a little of the hot cream mixture into the eggs, whisking the entire time, you don't want the eggs to cook. Continue adding the cream a little at a time until all is mixed. Then, return the mixture to the pot and return to a low heat. Whisk until it thickens, but be careful not to curdle the eggs. Remove from the heat, and stir in the butter and lemon juice. Sprinkle a thin layer of sugar on top and refrigerate.
make the Pate a Choux: Heat the milk or cream and butter over Medium heat in a heavy pot until it comes to a boil and the butter is melted. Then stir in the flour, sugar, and salt. Mix it with a wooden spoon. Keep stirring to keep it from sticking to the bottom of the pan. It will come together to form a ball of dough. Continue cooking for a couple minutes, stirring as need, to cook the flour and remove excess moisture. Remove from the heat and transfer to an electric mixer. Mix the dough at a medium speed. Add in the eggs, one at time until they are all incorporated. The mixture will be a sticky beige batter.
Preheat the oven to 400.
Line sheet pans with parchment paper and spray with pan spray. Put the Choux paste into a pastry bag with a plain tip. Pipe the paste into quarter sized mounds on the parchment. If you want to make eclairs, pipe it into logs. Space the mounds at least an inch apart, so they have room to puff out. Once piped out, dip your fingertip in cool water and flatten the point left from where you pulled the pastry bag off the mound.
Bake the Puffs at 400 degrees for 30 to 35 minutes. They should be golden brown and semi-hollow inside. Air cool them.
Make the Whipped Cream: Whip the Cream in an electric mixer or by hand until it begins to stiffen. Then add in the sugar and vanilla. Whip until it holds its shape, but don't over-whip or it will begin to break down and become butter. Keep this cold. Put in a pastry bag with a star tip.
Using a bread knife, carefully cut the puffs crosswise so you have a top and bottom for each.
Put the pastry cream and whipped cream into pastry bags. Pipe a little of the pastry cream on the bottom halves of the cream puffs. Then pipe the Whipped Cream vertically on top of that. Top with the top half of the puffs. Then re-warm the caramel and drizzle over each. For an extra touch, you can also sprinkle with powdered sugar and top with a couple grains of flaked sea salt. Refrigerate for at least 15 minutes. Serve cold.
