Preheat the oven to 150 C / Gas 2. Generously grease a 29x34x6.5cm (11.5x13.5x2.5in) t-shirt cake tin and line the base with a sheet of baking parchment cut to size.
In a bowl, cream the butter or margarine together with the sugar until light and fluffy. Beat in the eggs, one at a time until the mixture is pale and creamy. Sift in the flour and fold until well integrated, gradually adding the milk. Pour into the prepared cake tin, filling only half way to allow for a good rise.
Bake in the preheated oven for 60 minutes, then increase the oven temperature to 180 C / Gas 4 and cook for a further 60 minutes or until risen and golden and a skewer inserted into the centre comes out clean (avoid opening the oven door during cooking to prevent the cake from sinking in the middle). Remove from the oven and allow to cool for 10 minutes in the tin.
Carefully run a small knife around the edges of the cake to loosen. Lay a cooling rack on top of the tin and in one swift motion flip upside down allowing the cake to drop gently onto the rack; allow to cool completely.
Transfer the cake to a cake board. To decorate similar to the photo, spread a little vanilla icing over the cake then roll out the fondant icing and lay carefully on top, making small indents and cuts where needed around the neck and sleeves to bring the icing down around the sides. Trim off any excess and discard. Attach any edible logos with a little water. Serve!
I hope this t-shirt cake recipe is helpful to you.