Unfortunately I didn't take enough photos during the painting process to make this a proper demo. But you can see the cadmium orange underpainting and how that influenced the background.

My typical process is:

1. Underpainting
2. Let the underpainting dry to the touch
3. Alla-prima block in, putting as much finish on it as possible
4. Let that dry, then come in with finishing touches as necessary

The palette for this piece:

Permalba white
Ivory Black
Cadmium Orange
Cad Yellow Light
Permanent Red Medium
Alizarin Crimson
Burnt Umber
Sap Green

That's it. I try to keep my palette fairly simple for each painting - for me, the fewer the colors the more harmonious the end result. To make the palette even simpler, I could have used a mixture of ivory black, yellow, and white to make a dull green for the background instead of Sap Green (remember that ivory black is actually deep, muted blue). But I really wanted to set off Alison's skintones so a more vibrant green is what I chose for the background.