Vanilla is traditional, but any ice cream flavor or a combination can be used.
Position a rack in the lower third of the oven. Preheat the oven to 400°F. Have ready an unbuttered baking sheet.
Prepare:
      1/2 recipe Choux Paste
Scoop the paste into a pastry bag fitted with a 1/2-inch plain tip. Shape the paste into 24 profiteroles on the baking sheet, as directed in About Forming Choux Paste. Bake the profiteroles for 15 minutes. Reduce the oven temperature to 350°F and continue to bake until golden brown and very firm to the touch, 10 to 15 minutes more. Turn off the oven. Poke the bottom of each profiterole, turn upside down on the baking sheet, and let dry in the oven for 10 minutes. (Read About Choux Paste,  for more drying information.) Remove to a rack and let cool to room temperature.
Prepare:
      Chocolate Ganache Glaze or Frosting
Whisk the glaze until smooth. If desired, thin it with a little:
      Heavy cream
Keep warm in the top of a double boiler (or reheat in a microwave just before serving).
To serve, slice the profiteroles horizontally in half. Remove any uncooked dough. Place 4 bottoms on each of 6 plates. Place a small scoop of:
      Vanilla ice cream (enough for 1 scoop per profiterole)
in each bottom half. Cover with the top halves and drizzle with some of the chocolate glaze. Serve immediately with the remaining glaze on the side.