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, add bubble-gum or strawberry flavouring and pink food dye and mix for another 20 seconds. You will need to scrape down the bowl again and mix until the batter is evenly coloured.
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.
To prepare bubble-gum goo, add white choc and cream to a microwave safe bowl and microwave for 20 seconds at a time, mixing each time until smooth. Add blue food gel and flavouring and mix until well combined.
To finish off cupcakes, core the centre of each one and fill with bubble-gum goo. Fit the end of a piping bag with a round tip and frost your cupcakes in a flat swirl as demonstrated in the video. Coat the frosting in pink sprinkles, starting with the top of the frosting and then work your way around the sides of the frosting.
Finish off by gently placing your gelatin bubble in the frosting.