Preheat your oven to 180ºC/160ºC fan and line a 12 hole muffin tray with large cupcake cases/muffin cases.
Cream together the unsalted butter and caster sugar with an electric beater until smooth.
Add in the eggs, self raising flour and vanilla extract and beat again for about about 20-30 seconds on a medium speed – it really doesn’t take too long, you don’t want to overheat it!
Fold through the sprinkles and make sure they're evenly dispersed.
Spoon into your cases and bake in the oven for 18-20 minutes or until cooked through! Then, leave to cool completely on a wire rack.
Vanilla Buttercream Frosting
Beat the softened unsalted butter until smooth – this can take a couple of minutes.
Add in the icing sugar 1/3 at a time, making sure the sugar is fully incorporated until moving on. I use my KitchenAid for frostings as the machine can make it so much lighter and fluffier - but you don't have to!
Once all of the icing sugar is in the frosting mix, keep on beating the frosting but add the vanilla extract and the whole milk 1 tbsp at a time until you reach your desired consistency, I usually use about 3 spoonfuls!
Decorate your cupcakes how you like (I use lots and lots of sprinkles), and ENJOY!
Notes
As mentioned in the recipe, you need to use BRIGHT sprinkles - if you don't the sprinkles will fade and won't be shown in the cupcake, or the sponges will just turn and odd colour!
These cupcakes will last in an airtight container for 2-3 days, or you can freeze them for up to 3 months!