Here goes. The background was one I had already created unsing Corel Painter X. the rest is in Essentials 4
The Onion was drawn lightly with a 2B pencil adding a little shade to the areas I wanted to darken.
I then chose a limited pallette goverened by the limited range of colours in E4
French Ultramarine, French Rose, Alizarin red, Fire engine red and black.
I put these on the mixer board and created variying shades which I chose as needed with the 'sample colour' tool in the mixer set.
I used wet acrylic in varying opacities slowly building up the colour
One problem was that I found that the lower opacities painted white unless I added pressure and then it was often darker than I wished.
The shadow was much darker than I wanted to I used the freehand lasso tool, feathered to 10, and a soft focus. I wished I could find a blur tool but I don't think there is one.
I am sure there is possibly and easier way of doing things but I have never had any art training so I just keep fumbling along until I get to something I think is acceptable. Any tips on making it more realistic would be welcome.