Or temporarily cooling off. The Gainesville Ripper, Danny Harold Rolling, committed a triple homicide in Shreveport, LA in November 1989 and did not resume killing again until August 1990 in Gainesville FL.
After re-reading her autopsy report, I think a chef's knife has the right dimensions for the deepest wound (~3.5 in deep by 1.5 inches in length) found on her lower back. A lot of people own these knives, not just chefs, but I'm not ruling out the possibility of an acquaintance in the restaurant business. I just hope for her own sake that the killer was not someone she loved or trusted.