The act of painting one's toilet bowl with excrement from a vicious bowel movement. The resulting feces should usually be watery yet sticky enough to cling to the front, back, sides and sometimes the undercarriage of the bowl itself. The aforementioned splatter pattern created from the BM simulates the painting style of one Picasso for whom the name is obviously credited.
Can also be used in the context, "to Picasso", or "Picasso'd" for past tense usage.
"The toilet is my easel and I'm Picassoing a master piece thanks to Taco Bell!!!"
"I'm sorry man but I just totally Picasso'd you're toilet."
"Get the fuck out of the way, I'm about to Picasso."