First, prepare the pastry cream. Please see recipe link above.
Second, prepare the Choux pastry: Preheat oven to 400°F.
Take out the pan from the heat.
Put the hot dough in a bowl.
Beat the eggs, and add them gradually to the dough.
Mix well with a wooden spoon. The mixture may not look nice, but keep mixing.
Mix until you obtain a smooth glossy dough. The dough should be similar to a very thick liquid.
Place the dough in a pastry bag fitted with a large round tip.
Pipe onto a baking sheet lined with parchment paper.
Make thick line shapes of about 4 inches long, leaving 2 inches of space between them.
Gently brush with egg wash.
Prick the pastry shells with a toothpick in two or three places to allow vapor to escape.
Place the bowl over simmering water (Bain Marie or water bath).
Mix well the ingredients with a wooden spoon until you obtain a nice shiny ganache. Set aside.
Pipe in each choux pastry shell the pastry cream. You may need to make a little opening in the shells lengthwise.
Dip the top of the shells in the chocolate ganache.
Chill uncovered to set the ganache.