1Grease and line the bottom and side of a 8-inch round cake pan with parchment paper.
2Insert the wire rack into the middle shelf position. Preheat the oven. Set the oven BAKE/350°F/CONVECTION/45 minutes.
3To make the cake, put the butter, sugar and vanilla in the bowl of a stand mixer with the paddle attachment. Beat on medium speed for 2-3 minutes until mixture is pale and creamy.
4Add the eggs one at a time, beating well after each addition, and occasionally scraping down the side of the bowl.
5Turn the mixer to low speed, add half the flour, and then half the milk and mix until just combined. Repeat with the remaining flour and milk until incorporated.
6Scrape the batter into the prepared pan and level the top.
7Once preheated, put the cake in the oven and bake for 45 minutes until a skewer inserted into the center of the cake comes out clean.
8Cool the cake in the pan on a wire rack for 10 minutes, then turn the cake out onto the rack to cool completely.
9To make the whipped vanilla icing, sift the powdered sugar into the bowl of a stand mixer. Add the butter, water and vanilla. Beat with the whisk attachment on medium speed until well combined. Increase the speed to high and beat until a smooth, spreadable consistency is achieved.
10Spread the icing over the cooled cake. Slice and serve.