Set your oven nice and gentle at 160°C, 320°F. Prepare a 6-inch round tin, about 3 to 4 inches deep, by lining it carefully with parchment. Have all your ingredients at room temperature, this makes all the difference for a tender crumb.

In a mixing bowl, whisk together the egg yolks with 50 grams of sugar for about a minute, just until it turns a little pale. Add the oil, vanilla, salt, milk, water, fresh lemon juice, and a touch of zest. Stir patiently until everything is smooth and well blended.

Now take your cake flour and baking powder, sift them well, at least three times, so the mixture stays light as air. Gently fold the dry ingredients into the batter, taking care not to overwork it.

In another bowl, clean and completely dry, begin whipping the egg whites. Let them foam for a minute, then add a little cream of tartar or a few drops of lemon juice. Continue beating, and slowly sprinkle in the remaining sugar. Keep whisking until the meringue stands in firm, glossy peaks, this should take about five to six minutes.

Lighten the batter by folding in the meringue in three additions. Use a spatula and a gentle hand, turning the mixture rather than stirring, so you keep all that precious air inside.

Pour the batter into your prepared tin and smooth the top. Bake for about 55 to 58 minutes. The cake is ready when a toothpick inserted in the center comes out clean.

As soon as it leaves the oven, turn the tin upside down and let the cake cool completely in this position. This helps it stay tall and fluffy.

For the blackberry glaze, place fresh blackberries with a squeeze of lemon juice in a heatproof bowl and warm them in the microwave until they soften and release their juices. Strain the mixture to get a smooth puree, then stir it into confectioners’ sugar. Add a splash of vanilla and mix until you have a silky glaze. If it feels too thick, loosen it with a teaspoon or two of water. If too thin, add a little more sugar until it coats nicely.

Once your cake has cooled, pour the glaze over the top and spread it gently so it drapes beautifully.

To keep the cake, cover it well and leave it at room temperature if you plan to enjoy it within a day. For longer storage, place it in the refrigerator, always covered so it does not dry out. It also freezes quite well for up to two months, just let it come back to room temperature before serving.

As for baking a chiffon without a tube pan, for a small cake like this, it works just fine. You will still get that soft, airy texture. For a larger cake, though, I would not risk it, as it may dry out before baking through properly.