Remove sides of bell peppers and discard stem and seeds. Roast for 10-12 minutes, or until edges begin to brown. Let cool.
Combine ingredients in a container with tall sides and mix with immersion blender until smooth and all ingredients are evenly distributed.
Place 15 empty cups in a 4-inch plastic full pan and pour 9 fl oz smoothie into each cup. Cover cups with lids. Pans of smoothies can be stacked and held in the cooler until ready to serve. Hold smoothies cold at 41F or lower. Modifications: Smoothies can be made with a variety of canned fruit.