This is perhaps my favourite set of ATCs. And I didn't use PhotoShop. Instead, I bought lots of canned soup, tore off the label and cut out the actual soup part in the bowl. I replaced the soup with bits of art. Or I put bits of art into the soup. It depended on what worked best. Cream of famous artists soup! All those years of art history classes finally paid off.
And check out Cream of Oppenheim. It's a play on her Fur-Lined Tea Cup, considered one of the archetypal works of the Surrealist movement. In this case, it is the Fur-Lined Soup Bowl (and I used a tiny piece of real fur).