Combine first 5 ingredients in food processor. Pulse until smooth. Spread bean mixture evenly over crust. Top with red onion and next 4 ingredients. Bake at 450° for 12 to 15 minutes. Top with arugula, if desired.
Note: For testing we used Mama Mary's Gourmet Pizza Crust.
I liked this quite a bit. I used dried oregano instead of fresh and I carmelized the onions to make them milder. Also made it on the grill instead of the oven since AZ summers are so hot. One has to really like anchovies to enjoy this.