Step 1
Preheat oven to 425 degrees F (220 degrees C). Line 2 baking sheets with silicone baking mats.
Step 2
Stir water butter 1 teaspoon white sugar and salt together in a pot; bring to a simmer. Add flour and stir with a wooden spoon until mixture pulls away from the sides of the pot and forms a thick paste-like dough. Remove from heat and let cool for 10 to 15 minutes.
Step 3
Stir eggs into dough one at a time mixing until egg is completely incorporated after each addition. Transfer 2/3 the dough to a large resealable plastic bag. Cut corner of the bag away about 1/2-inch wide to form an opening through which to pipe the dough.
Step 4
Pipe 8 tapered ovals of dough onto the prepared baking sheet to form the 'swan bodies' pulling up at the tapered end to form the 'tail/wingtips'.
Step 5
Bake in preheated oven until golden brown 20 to 25 minutes.
Step 6
While the 'swan bodies' are baking fill a smaller bag with with the remaining 1/3 the dough; cut a small tip from the corner. Pipe out S-shapes to form the swan 'necks'. At the top of each S pipe out more dough to form the swan 'heads'.
Step 7
When the 'bodies' are halfway cooked bake the 'necks' in the oven together with the swan 'bodies' oven until golden brown 10 to 12 minutes.
Step 8
Turn off the oven open the oven door slightly and let pastries cool completely.
Step 9
Cut the top 1/3 off of each swan body horizontally from fatter end to tapered end. Cut each top in half to form the 'wings'.
Step 9
Place chocolate in a heat-proof bowl. Bring 4 ounces heavy cream to a boil in a small saucepan. Pour hot cream over chocolate and whisk until chocolate is completely melted and ganache is shiny and smooth. Spoon or pipe chocolate ganache into the base of each swan 'body'.