Preheat the oven to 180°C (160°C for fan assisted ovens)/Gas Mark 4. Grease and lightly flour a 2.4 litre capacity bundt tin.
Put the cake mix in a large mixing bowl and add the oil, water, eggs and soft cheese. Beat with an electric mixer for 2-3 minutes until smooth and creamy. Spoon the mixture into the prepared tin and gently level the surface with a spatula. Bake for 40-45 minutes until a skewer inserted into the cake comes out clean. Leave to cool for 15 minutes.
Meanwhile, make the strawberry puree. Place all the ingredients in a food processor or blender and process until smooth. Transfer to a small jug.
With the cake still in the tin, use the end of a wooden spoon to poke holes into the cake at 1-2cm intervals, going almost to the bottom. Carefully pour the puree into the holes. If necessary poke existing holes again to make room for more puree. Leave the cake to cool completely then cover and chill in the refrigerator for 2 hours.
Run a spatula around the inside edge of the tin to loosen the cake then invert onto a serving plate.
To decorate the cake, beat the icing and milk in a small bowl together until smooth. Spoon into a disposable piping bag and snip off the end. Drizzle the icing in a zig-zag pattern over the cake and top with the sliced strawberries.