In a large mixing bowl, combine the room-temperature whipping cream and the sifted low-gluten flour. Using a silicone spatula, mix until just combined and no dry flour remains.

Add the three room-temperature egg yolks and mix until the batter is perfectly smooth, thick, and homogeneous. Place this bowl over a pot of warm water (around 50°C / 122°F) to keep it gently warm and fluid while you prepare the meringue.

Place the clean, grease-free bowl of egg whites into the freezer for about 10 minutes, until the edges just begin to show tiny ice crystals. This chills the proteins and helps create a more stable meringue.

Remove from the freezer. Add the lemon juice and all of the fine granulated sugar at once to the egg whites.

Using an electric mixer on high speed, whip until the meringue reaches a soft peak stage: when you lift the whisk, the peak should curl over gently like a bird's beak. Do not whip to stiff, upright peaks.

Add about one-third of the whipped meringue to the warm yolk batter.

Gently fold it in by cutting down the middle and scooping from the bottom up and over. This preserves air bubbles.

Once mostly incorporated, pour this mixture back into the bowl with the remaining two-thirds of the meringue. Continue folding gently and quickly until no white streaks remain and the batter is uniform. Avoid stirring or beating.

Preheat your oven to 140°C (285°F). Prepare the water bath: Take your chiffon cake mold (do not grease it) and tightly wrap the outside bottom and sides with aluminum foil.

Pour the cake batter into the mold.

Gently tap it on the counter a few times to release large air bubbles.

Place a deep baking tray on the lowest rack of your oven and carefully fill it with about 2 cm of hot water.

Place the foil-wrapped cake mold directly on the oven rack in the middle position, ensuring it is not sitting in the water tray—this creates a steamy environment without direct contact.

Bake at 140°C (285°F) for 30 minutes, then increase the temperature to 150°C (300°F) and bake for an additional 28-30 minutes. The cake is done when the top is golden, springs back lightly to the touch, and a skewer inserted comes out clean.

Immediately upon removing the cake from the oven, drop the mold from a short height onto the counter once to shock it and prevent severe shrinkage.

Invert the mold immediately by balancing it over the neck of a bottle or on a cooling rack. Let it cool completely upside down (this takes about 1-2 hours). Once completely cool, run a thin, flexible knife or offset spatula closely around the inner tube and outer edge of the mold to release the cake gently.