I never tire of the classic diner still life. There's always about a 15-20 minute time limit from when the order goes in to when the food is on the table. The time limit focuses the brain better than coffee does.
The humble catsup bottle, sugar shaker, napkin holder, and creamer are an interesting challenge to paint, because they offer a variety of transparent and reflective surfaces: stainless steel, glass, and paper. And there's the catsup creeping up the side of the bottle, backlit and warmed with transmitted light.
What interested me this time were the two colors of light on the subject. From the left was a cool light the window, which mostly looked out to the blue sky. The light inside was from a relatively warm compact fluorescent. So my first move after laying in the subject in pencil was to lay down a ghost wash to establish the overall cool and warm statement, being careful to paint around the highlights.
I hope all this make sense. I would show you a video, but I was too preoccupied to shoot one.
Technical notes: The painting is done with a half pan watercolor set in a watercolor notebook. I used two flat watercolor brushes: 1 inch and 1/4 inch, with a few dark accents from watercolor pencils.