The Vanilla Cupcake
Preheat the oven to 160°C (315°F/Gas 2–3). Combine the dry ingredients together. Using an electric mixer, beat the eggs, vanilla and zest on a high speed until light and fluffy. Whisk the softened butter and sugar together vigorously, then alternately add the combined dry ingredients and the egg mixture. Carefully combine. Fill silicon moulds or two muffin tins with paper liners and divide the batter between them. Cook in the oven for about 25 minutes. Allow to cool. Turn out the cupcakes and spread frosting on each one using a spatula.
The Vanilla Frosting
Beat the butter and sugar together in a food processor or with a spatula until smooth. Add the milk and the vanilla bean seeds and mix again vigorously in the processor or with the spatula for at least 5 minutes. The mixture will become creamy and is then ready to use.