Tea party birthday cake

There was a birthday this week in our house (my husband's) and I made this cake for him. As you can see, I just about managed to snap a few photos before it got polished off. I'm sharing the recipe because it's so simple to make, and quick too. I decided to make this and...
less than 2 hours later we were eating it, still ever so slightly warm. It's a chocolate cake with chocolate chips that I adapted from a Jamie Oliver cake recipe and a butter frosting in between the layers and on the top.

Ingredients
Cake
3 tbsp cocoa powder
1 cup sugar
7 oz butter
3 eggs
1 2/3 cups self-raising flour
1 tsp baking powder
1/2 cup mini chocolate chips

Butter Frosting
1/2 cup butter
3 cups powdered sugar
1/4 cup milk
2 tsp vanilla extract

Preheat the oven to 350 degrees and line the bases of two 8" cake tins with brown paper or parchment paper.

Mix the cocoa powder into 5 tbsp of boiling water and stir thoroughly.

In a mixer, beat the sugar and butter until light and fluffy. Add the cocoa mixture, eggs, flour and baking powder. Fold in the chocolate chips and divide the mixture evenly between the two cake tins. Bake for about 30 mins and allow to cool.

For the butter frosting, beat the butter until light and fluffy and gradually add the sugar. Slowly add the milk and vanilla extract and beat until smooth. Spread it between the two layers of cake and on the top. Add a few sprinkles to decorate.