Step 1

Before you start. Preheat the oven to 175°C (350°F) and position an oven rack in the lower half of the oven so that when you place the pan, it will be in the center of the oven. Grease the base and sides of a 20 x 20 x 8 cm (8 x 8 x 3 in) cake pan with butter. Dust lightly with flour and tap out the excess.

Step 2

Sift the dry ingredients: Sift flour with salt twice (omit salt if using salted butter).

Step 3

Whip up the egg whites: In a stand mixer fitted with a whisk or with handheld beaters, whip egg whites on medium-high speed (speed 4 on Kitchen Aid mixer). Once whites get foamy, stop the mixer and sprinkle baking powder. Turn the mixer on, and whip for 5 - 10 seconds to combine well. Next, add sugar a little bit at a time and continue whipping at medium-high speed until the egg whites become thick, glossy, and form stiff peaks.

Step 4

Beat in the egg yolks: Beat the egg yolks lightly with a fork. Now reduce the mixer speed, and drizzle in the yolks, 2 to 3 tbsps at a time. After adding all the yolks, continue whipping for 30 seconds until thick and creamy. Pour out into another large mixing bowl. Clean and dry the mixer bowl thoroughly for the next step.

Step 5

Cream butter and condensed milk: In a stand mixer fitted with a paddle or with handheld beaters, beat butter and condensed milk on medium speed (speed 3 on my Kitchen Aid mixer) until light and fluffy, about 5 minutes.

Step 6

Beat in extracts and brandy (optional): Add the vanilla extract, almond extract, and brandy (if using) and beat for 15 seconds to combine well.

Step 7

Beat in the whipped eggs mixture: Add one cup of the whipped eggs mixture and beat for 30 seconds until well mixed.

Step 8

Fold in the flour mixture and remaining eggs mixture: Tip in all the flour mixture, followed by the rest of the whipped eggs mixture all at once. Without starting the mixer, fold lightly by hand to combine the wet and dry mixtures. Then start the mixer at the lowest speed. Beat until the batter is smooth and even, about 20 - 25 seconds. Stop the mixer and remove the bowl. Finish folding the cake batter by hand, until it is smooth and is at the same consistency throughout. (Alternatively, you can fold the batter entirely by hand.)

Step 9

Pour the batter into the prepared cake pan. Spread it to the sides and corners of the pan, and level the surface evenly with an offset spatula. Bake at 175°C (350° F) for 10 minutes. Reduce oven temperature to 135°C (275° F) and bake for a further 60 to 75 minutes. Note: This cake needs to bake slowly and for a longer period of time.

Step 10

To test for doneness, press the center of the cake gently with your fingers. If it feels firm and springs back, it is done. Also, test with a metal skewer by inserting into the centre of the cake. It should come out clean without any sticky batter. Remove the pan from the oven and place on a wire rack. Let cool in the pan for 10 to 15 minutes, then turn out onto a wire rack to cool completely.