Calvin and Hobbes by Bill Watterson for March 26, 1994
Calvin: These colors really aren't enough, so I have to mix some to get the specific hues I need. See, here I start with a layer of brown. Then I add olive green and scrub a little orange and yellow ochre into it. Finally, I top it with lime green, purple, and tan. Hobbes: Wow, perfect barf! Calvin: You'd think that would be a standard color in a big set like this.