Preheat the oven to 180°C(160°C fan) for 20 minutes before starting the batter. Place the shelf in the middle of the oven.
Grease 2 x 20cm / 8” cake pans with butter, then line with parchment/ baking paper. Best to use cake pan without loose base, if you can.
Whisk flour, baking powder and salt in a large bowl. Set aside.
Beat eggs for 30 seconds on speed 6 of a Stand Mixer fitted with a whisk attachment, or hand beater.
With the beater still going, pour the sugar in over 45 seconds.
Then beat for 7 minutes on speed 8, or until tripled in volume and white.
Heat Milk-Butter: While the egg is beating, place butter and milk in a heatproof jug and microwave for 2 minutes on high to melt butter (or use a stove). Do not let milk bubble and boil (foam ok). Don’t do this ahead and let the milk cool (this affects rise).
Gently add flour: When the egg is whipped, scatter 1/3 flour across the surface, then beat on Speed 1 for 5 seconds. Add half the remaining flour, then mix on Speed 1 for 5 sec. Add remaining flour, then mix on Speed 1 for 5 - 10 sec until the flour is just mixed in. Once you can’t see flour, stop straight away.
Lighten hot milk with some Egg Batter: Pour hot milk, vanilla and oil into the now empty flour bowl. Add about 1 1/2 cups (2 ladles or so) of the Egg Batter into the Milk-Butter (don't need to be 100% accurate with the amount). Use a whisk to mix until smooth - you can be vigorous here. Will look foamy.
Slowly add milk: Turn the beater back on Speed 1 then pour the Milk mixture into the Egg Batter over 15 seconds, then turn the beater off.
Scrape and final mix: Scrape down the sides and base of the bowl. Beat on Speed 1 for 10 seconds - batter should now be smooth and pourable.
Pour batter into pans.
Knock out bubbles: Bang each cake pan on the counter 3 times to knock out big bubbles.
Bake 30 minutes or until golden and a toothpick inserted into the centre comes out clean.
Remove from oven. Cool in cake pans for 15 minutes, then gently turn out onto cooling racks. If using as layer cakes, cool upside down - slight dome will flatten perfectly. Level cake = neat layers.
Frost with frosting of choice, or cream and fresh berries or jam.