My initial thought was to paint something with a very strong emphasis on lighting; a moody environment with lots of depth and contrasting colours. I wasn't too concerned about the subject matter, except that it had to be organic and a little abstract so I could easily change, adjust and cheat the lighting. I do enjoy direct lighting and an environment heavy in atmosphere, so that's what I was trying to achieve in this painting. The process was more or less how I paint most of the time; I tried to use the majority of my usual techniques and methods in order to show how they help with the process.
After a number of quick scribbles for some ideas, mostly to sketch up something that would cater to my needs, I decided to go ahead with this one - can't go wrong with exotic mushrooms! It wasn't the most solid sketch, but it would do for a start as the sketch was only a guide (Fig.01).
The next step was to block in some quick colours, but more importantly, I had to work out the light source and the overall mood of the environment. I wanted to play up the reflecting light from below with warm lighting, assuming that the top of the mushroom caps were warm coloured. I ran the lighting through the centre and added depth to the valley with mushrooms (Fig.02).
Here I added a new layer on top, and continued to block in and shape the mushrooms. I introduced some cooler diffuse lighting from the left, as this helped to lighten some of the darker areas. I flipped the image horizontally a lot, to check that nothing was too out of place, and I also often worked on the flipped image for a bit before flipping back (Fig.03).
At this point it was time to add in some random textures to help with the rendering process. Some photo textures were used to spice things up a little and to help speed up the process. The textures were just some fig tree trunks, which I placed on top as Overlay layers. This probably doesn't show in the final image, as it was used more as a guide - I just picked some random shapes from it (Fig.04).