According to the highest authority (Wikipedia), there are very few people, even Muslims who should find this offensive. Muhammed, the Muslim prophet, is sharing a cookie with Jesus, the Christian Savior.
Sunnis are the largest group of Muslims to be concerned with portrayals of the prophet Muhammed, mainly because they fear that it would cause idolatry, the worship of an image over the idea behind it. That is completely rational, and I respect that. But it is not a written in Qu'ran, and bans against it are only ever found in supplemental texts, and resemble the Jewish traditional ban on "graven images".
Persian and Ottoman Muslims over the centuries have created many beautiful works of art depicting Muhammed in a historical light. The Supreme Court Building in Washington DC depicts Muhammed along with Hammurabi and Moses as a Judge and Rule-maker. Devotional and historical films have been made about Muhammed. And in my opinion, yeah, the Dutch cartoons of Muhammed were kind of insensitive, and in my opinion, kind of not funny either. Maybe that's what passes for humor in the Netherlands.
So to anyone who threatens me with violence over a heavily stylized depiction of Muhammed with a cookie: Fuck you.