Profiteroles with Chocolate Sauce

Combine the water, diced butter, salt, and sugar in a heavy saucepan. Set over medium heat and stir occasionally until the butter melts completely. Increase the heat and bring to a full, rolling boil — every bubble breaking the surface. Do not let it reduce; have the flour ready and act immediately when it boils. A partial boil is not sufficient — the entire liquid must be at a true boil when the flour goes in, or the starch will not cook properly.

Tip all the flour into the boiling liquid at once. Stir immediately and vigorously with a wooden spoon — the mixture will seize into a rough, shaggy mass, then smooth out within 30 seconds into a ball. Return to medium heat and continue stirring, pressing the paste against the bottom of the pan, for 1 to 2 minutes to dry it out — a thin skin should form on the pan base. Transfer to a stand mixer bowl or large bowl and beat briefly to cool, then add the beaten eggs in 6 to 8 additions, beating well after each. Stop when the paste falls from the beater in a slow V and holds its shape when piped.

Preheat the oven to 200°C (390°F). Pipe the choux paste onto lined baking sheets in rounds of about 3 cm diameter, spaced 5 cm apart. Wet a finger and smooth any peaks. Bake for 20 to 25 minutes until puffed, deeply golden brown, and rigid. Do not open the oven in the first 15 minutes. After the puffs are golden and holding their shape, reduce the heat to 170°C and bake for a further 5 minutes to dry the interior. Transfer to a rack and pierce the base of each puff with a skewer to release steam. Cool completely before filling.

Heat half the heavy cream in a small saucepan to just below a boil — wisps of steam and a quiver of surface movement, no rolling bubbles. Pour the hot cream over the finely chopped dark chocolate in a heatproof bowl and leave undisturbed for 90 seconds. Stir from the centre outward in slow circles until the ganache is completely smooth and glossy. The sauce should be pourable and warm but not runny — if too thick, add a splash of cream. Keep warm over a pot of hot water.

Using cold cream, cold bowl, and cold beaters, whip the remaining heavy cream with the vanilla extract to firm but not stiff peaks — it should hold its shape when piped but feel airy, not grainy. Transfer to a piping bag. Make a small incision in the base of each puff with a serrated knife and pipe in the cream until the puff feels noticeably heavier. Arrange in a bowl or on a plate, pile generously, and pour the warm chocolate sauce over at the table so guests hear the sauce hitting the cream. Serve immediately.