Preheat the oven to 180˚C/160˚C fan/gas mark 4. Line a 12 hole muffin tin with half red and half blue Dr. Oetker Rainbow Cupcake Cases.
In a large bowl, beat together all the cupcake ingredients until smooth.
Spoon the mixture into the baking cases and bake for 15-20 minutes. Allow to cool completely.
For the Chocolate Fireworks, melt the white chocolate according to packet instructions.
Divide the White Chocolate into 3 bowls. To one bowl add a few drops of Dr. Oetker Blue Extra Strong Food Colouring Gel and to another bowl add a few drops of Dr. Oetker Red Extra Strong Food Colouring Gel. Stir and add more gel until you reach your desired colour. Leave the remaining colour white.
Line a baking tray with non-stick parchment paper. Spoon each colour into separate piping bags and cut a small hole at the end of each bag.
On the prepared tray, drizzle each colour of white chocolate in a firework shape, overlapping each of the colours. Place in the fridge and allow to set for 5-8 minutes.
Once the cupcakes are cooled, use a teaspoon to remove some of the middle of each cupcake. Add 1 teaspoon of popping candy into each cupcake.
Soften the Dr. Oetker Vanilla Buttercream Style Icing in the tub by giving it a quick stir with a spoon. Add the buttercream to a piping bag with a large star nozzle. Swirl the buttercream on top of each cupcake.
Remove the White Chocolate Fireworks from the fridge, once set. Stick the Fireworks standing up on the top of each cupcake.