The easiest and bestest chocolate cupcakes

A first birthday happened a couple of months ago, and it completely skipped my mind. (School holidays will do that to your brain.) It’s been over one year since I started once upon an egg (with this post), and 81 posts later, I’m happy to say I’m still going. This blog has been a big learning curve; I’d never worked behind the scenes on a website before, I’d never edited a photo, or styled one for that matter, and I’d never written anything that strangers could, and would, read. I’ve learnt about photography, when is the best time to publish a post, and how to improve my instagram game. I’ve learnt that it’s probably best to give away most of what I bake. And I’ve learnt that I can do this.

What better way to celebrate a birthday than with the most delicious chocolate cupcakes. These cupcakes are great because you don’t need a cake mixer (except for the buttercream.) I’m a big fan of anything that can be just mixed in a bowl. For an added treat, I like to scoop out the centre of each cupcake while they’re still hot and pop in a marshmallow, resulting in a melty surprise when you bite into it. And the buttercream? That’s just one big pile of creamy, dreamy, chocolatey goodness.

Happy birthday, once upon an egg.

For the cupcakes


3oz dark chocolate, roughly chopped (I used 70%)
1/3c cocoa
¾c hot coffee
¾c flour
¾c sugar
½ teaspoon baking soda
6 tablespoons vegetable oil (I used rice bran oil)
2 large eggs (I used size 7)
2 teaspoons white vinegar
1 teaspoon vanilla extract
12 marshmallows, if using


Preheat your oven to 180°C and line a 12 cup muffin tin with liners.
Place the chocolate and cocoa in a heatproof bowl and pour off the hot coffee. Whisk until smooth and then refrigerate for 20 minutes.
In a large bowl, whisk together the flour, sugar and baking soda. Set aside.
Remove the chocolate and cocoa mixture from the fridge and into it whisk the oil, eggs, vinegar and vanilla.
Pour this into the dry ingredients and whisk until smooth.
Pour into the muffin tin (around ¾ full) and bake for about 18 minutes, or until a skewer comes out clean.

Remove from the oven and cool completely before frosting.

If you are adding the marshmallows, you will need to work while the cupcakes are still hot. Scoop a small amount of cupcake out, pop a marshmallow into the cavity and then squish the lid back on. It doesn’t need to be neat because it will be covered in frosting.


For the chocolate buttercream


180g dark chocolate, roughly chopped (I used 70%)
225g butter, cubed and softened
1 tablespoon milk
1 teaspoon vanilla extract
250g icing sugar


Using a double boiler or the microwave, melt the chocolate until smooth and glossy then allow to cool for 5 minutes.
In the bowl of a stand mixer fitted with the paddle attachment, beat the butter, milk, vanilla and icing sugar until smooth. Scrape down the side of the bowl when necessary.
Add the chocolate and beat again until the buttercream is thick.
Pipe or spread the buttercream onto the cupcakes. I used Ateco tip 849.


  • I find a melon baller is useful for scooping out for the marshmallow.
  • Cupcake recipe via The Brown Eyed Baker.

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