I put this shadow under the plate in a very wet mixture. While it was still damp, not completely dry, but wet enough to allow the edges of the paint to soften, I added some Perylene Green to the closest area under the plate.
This is where the shadow is the deepest and darkest in value because it is the most hidden from the light source. Just a touch goes a long way. I want to keep the majority of the shadow in the brown tones.
Here you can see I have added some of these colors to the plate and bowl as these will be reflecting onto the clear and white shiny surfaces.