Preheat oven to 400 degrees. Line three sheet trays with silicone baking mats or lightly greased parchment paper.
In a medium saucepan, mix butter, sugar, salt and water. Bring to a boil and immediately remove from heat.
Stir in flour and mix vigorously with a wooden spoon until the mixture is thick and well incorporated.
Once slightly cooled, add eggs one at a time, beating well after each addition.
When all eggs are well incorporated, place the mixture into 12-inch piping bags.
Pipe 5-inch choux eclairs onto one prepared baking sheet. Pipe 3-inch profiteroles onto one prepared baking sheet. Pipe the same number of 4 inch rounds and 1 ½ inch rounds onto the third prepared baking sheet.
Bake for 10 minutes, then lower oven temperature to 325 degrees and bake 30 minutes more, until golden brown.
Fill all pastries with pastry cream and dip the tops in chocolate.
Decorate the profiteroles with sprinkles, the eclairs with fruit and chocolate, and the religieuses by stacking them and piping around the outside with buttercream.
Tip #1: Egg sizes are different, sometimes you need to add more or less egg so if the mixture looks too loose mix it well and keep cooking it, you want it to be thick, glossy and pulling away from the sides of the pot.
Tip #2: Start the oven up high to help the choux puff. If you start the oven too low the shapes will not get lofty. Lower the oven after 10-15 minutes or so and bake the puffs low and slow so they dry out completely. If you don’t allow the puffs to dry completely they will have a chewy texture and deflate.
Tip #3: To fill eclairs use a thin piping tip and pipe the cream in three places rather than cutting the eclair open. This will create a seamless finish for the glaze.