Place tomatoes in the Vita-Mix container. Secure 2-part lid. Select VARIABLE, speed #1. Turn machine on and quickly increase speed to #10; then to HIGH. Run until smooth.
In a 4 quart pot, combine all ingredients except butter, flour and milk. Bring mixture to a boil. Reduce heat and simmer uncovered for 30 minutes. Remove bay leaf.
In a 6 quart pot, melt the butter; blend in flour until smooth and bubbly. Gradually add milk; bring to a boil over medium heat, stirring constantly. Cook two minutes, then reduce the heat, and gradually add the tomato mixture, stirring until smooth and heated through.
Place reserved plum tomatoes in Vita-Mix container. Secure 2-part lid. Select VARIABLE, speed #3. Turn machine on and quickly pulse the machine on and off about 3-4 times until tomatoes are chopped. Stir chopped tomatoes into soup mixture. Serve.