Preheat the oven to 180°C and butter an oven-proof dish.
Add the eggs and the sugar to a bowl of an electric mixer fitted with a whisk attachment. Beat at medium-high speed until the mixture is pale and airy.
Add the apricot jam, vanilla, and vinegar to the egg and sugar mixture and beat until combined.
Sift together the flour and salt and slowly add this flour mixture to the egg mixture with the mixer running at low speed. Scrape down the sides of the bowl to ensure that there are no lumps and mix again briefly.
Mix the milk and the bicarbonate of soda together in a jug. Slowly pour this into the batter with the mixer running. Mix until the batter is smooth and lump-free.
Pour the batter into the prepared baking dish and bake in a preheated oven for about 45 minutes or until golden brown and a skewer inserted into the centre of the pudding comes out clean.
Malva Pudding Sauce
To make the sauce, combine the water, sugar, evaporated milk, and butter in a small saucepan set over medium heat. Bring the mixture to a gentle simmer and allow the sugar and butter to melt.
Once the butter and sugar have melted pour the sauce slowly over the pudding as soon as it comes out of the oven.
Set the pudding aside to cool to room temperature.
Milktart
Add the condensed milk, milk and cinnamon stick to a medium saucepan set over medium heat. Heat until almost boiling.
Add the egg yolks and the corn flour to a bowl of an electric mixer fitted with a whisk attachment. Beat until just combined.
In a steady stream add the hot milk mixture to the egg mixture while whisking, do this slowly to temper the eggs. Continue until all of the milk has been added. Transfer the mixture to a clean saucepan set over medium heat.
Whisk continuously until the custard thickens and coats the back of a wooden spoon, once thick remove from the heat and whisk in the butter.
Pour the milk tart topping over the cooled malva pudding base, and smooth it out with a spatula. Cover the top of the dish with plastic wrap and press it down gently so that it is in contact with the custard. Place the milktart malva into the fridge to set for about 6 hours.
Once set, dust the top of the pudding with ground cinnamon, slice, and enjoy!