1.Open image in Photoshop.
2. Select the subject in the picture, copy into a new layer. Hide background layer.
3. Create a new layer and paste again, slightly off set it and adjust the brightness darker and contrast higher.
The cake didn't work that well as you can see the chocolate cake beneath the custard and there is an edge to the splatter marks where the cake finishes in the other layers. To improve this I would make sure that the cakes were in line and the the colours follow on from one another.
The jelly is my favourite edit as it is the more realistic one of the three. I like the way the disperse is spreading and the colours. The fact that it is all one colour, red, it makes it look like blood splatter which adds to the gruesomeness.