Guacamole- deconstructed....

Tonight we made one of Jamie's 15 minute meals. It took 2 of us half an hour.... Still, the end result was lovely. 'Mexican BLT' which turned out to be a baguette with bacon, home made guacamole, chicken breast and lettuce served with a feta, lettuce and radish salad and guacamole on the side. Well done Ellie. Tasty.
Now when I watch cookery programmes - which is often- there seems to be a craze for 'deconstructing' dishes. Cottage pie will be some mashed potato statue with mince in a ramekin .... you get the idea.
I decided to deconstruct the guacamole down to the ingredients. Unfortunately we had used all the real spring onions in the constructed version so a broccoli stalk had to surfice.
I am just starting in photoshop and swore a bit trying to get the background to select without the edges noticing too much. Maybe I am not patient enough.
Any tips gratefully received.