Use a round cutter or a patterned cutter (5cm in width) and cut out 20 circles. Place on a baking tray lined with baking paper. Place another sheet of baking paper on top and place a second baking tray on top. This is going to prevent them from rising. Bake on 200C for 20 min or until golden. Allow to cool completely the tray on top.
Pastry Cream Frosting
Add gelatin to a mixing bowl. Pour 4 tbsp water over it. Give it a stir and set it aside to bloom and soak up the water,
In a large mixing bowl, mix the yolks, vanilla bean paste and the sugar and whisk until well combined and the mixture lightens in color. Add the corn flour and plain flour and stir until mixture is smooth Add 1/3 of the hot milk and stir well. Then slowly add the rest of the milk while stirring
Transfer to a medium sized saucepan and stir on medium heat until mixture thickens and becomes smooth. You should be able to run your finger along the back of the spoon and it will be thick enough to not come back together.
Add the gelatin mixture to the hot custard and stir until it melts and dissolves completely, then add the cold butter cubes and stir until well combined.
Transfer custard to a bowl, cover with plastic wrap and refrigerate for at least 3-4 hours or overnight to allow it to completely set. Whip up again right before you’re ready to frost to get it to a nice smooth consistency.
To make thin custard filling, microwave for 1 min, take about 1 cup of custard and add 175ml warm milk to it. Stir until well combined.
Preheat a fan-forced oven to 160C (320F) or 180C (356F) for a conventional oven. Line a cupcake tin with cupcake liners.
In the bowl of a stand mixer fitted with the paddle attachment, add the flour, baking powder, caster sugar and salt. Turn mixer on low speed and allow it to mix for a couple minutes to help everything combine well (alternatively you may do this by sifting the ingredients together). Add the softened butter and let it mix until it resembles a fine sand like texture.
Next, add milk, eggs, yogurt, oil and vanilla extract in a large jug and whisk well.
Add wet ingredients to dry ingredients in a slow and steady stream until no dry ingredients are visible. Scrape down the bowl and mix for another 20 seconds.
Fill each cupcake liner 3/4 of the way (using an ice cream scoop to transfer the batter into the cupcake liners makes this a quick and easy process otherwise you can use two tablespoons).
Bake for 20-25 min or until a toothpick inserted comes out clean. Allow them to cool completely on a wire cooling rack before frosting.
Core the centre of each cupcake and fill with custard.
Fit the end of a piping bag with a Wilton #32 piping tip and pipe little bulbs around the cupcake. Add a pastry disc on top, followed by another layer of custard and a final pastry disc. Dust with icing sugar before serving.
Cupcakes can be stored in an airtight container for up to three days.