1. Preheat the oven to 350⁰F (180⁰C). Line a 12-cup muffin tin with cupcake cases.
2. Add 1/2 cup cocoa powder to 1/2 cup boiling water and whisk until completely smooth.
3. Let it cool for a few minutes while you get the rest of the batter together. It doesn’t need to be cold, just not piping hot.
4. In a large bowl, dry whisk 1 cup cake flour, 1 cup caster sugar, 1 tsp baking powder and 1/2 tsp bicarbonate of soda until evenly combined.
5. In another bowl, whisk 1/2 cup full cream milk, 1/4 cup sunflower oil, 1 large egg and 1 tsp vanilla essence until well combined and a little frothy.
6. Sift half of the dry mixture into the wet mixture and gently mix until mostly combined.
7. Add the slightly cooled cocoa and boiling water paste and mix until smooth.
8. Sift in the remaining dry mixture and gently fold or mix just until you no longer see streaks of flour. Don’t keep beating the batter once it’s combined or the cupcakes can lose some of that soft texture.
9. Divide the batter between the cupcake cases, filling each about 1/2 to 2/3 full. If you prefer taller cupcakes, go closer to 2/3 full, but don’t overfill them.
10. Bake for 15 to 20 minutes, or until the tops spring back lightly when touched and a toothpick inserted into the centre comes out clean or with a few moist crumbs attached.
11. Let the cupcakes cool in the tin for about 5 minutes, then transfer them to a wire rack to cool completely before icing. This bit matters. Buttercream on warm cupcakes is basically asking for trouble.

Chocolate Buttercream

1. Add 1/2 cup softened butter to a mixing bowl and beat until smooth and creamy.
2. Add 2 1/2 cups sifted icing sugar and 2 tbsp sifted cocoa powder gradually, beating well between additions.
3. Add 2 tsp vanilla essence and beat until the buttercream is light and fluffy.
4. Check the consistency. If it’s too stiff, add 1 tsp full cream milk at a time and beat again. If it’s too soft, add more sifted icing sugar, a spoonful at a time. You can also add a little extra cocoa powder if you want a deeper chocolate flavour.
5. Once the cupcakes are completely cool, pipe or spread the chocolate buttercream over the tops. I wouldn’t overthink it. A generous swirl is exactly what these need