1 head orange cauliflower, cut into small florets
6 cups chicken broth, divided
1 cup chopped onion, divided
1/2 teaspoon salt, divided
1/4 teaspoon black pepper, divided
1 head purple cauliflower, cut into small florets
1 cup half-and-half, divided
In a medium saucepan, combine orange cauliflower, 3 cups broth, 1/2 cup onion, 1/4 teaspoon salt, and 1/8 teaspoon pepper; set aside.
In another medium saucepan, combine purple cauliflower, the remaining 3 cups broth, 1/2 cup onion, 1/4 teaspoon salt, and 1/8 teaspoon pepper.
Bring both saucepans to a boil over high heat, then reduce heat to low and simmer 20 to 25 minutes, or until cauliflower is very tender.
Using a blender or immersion blender, puree each saucepan separately until smooth (return to saucepans, if using a standard blender). Stir 1/2 cup half-and-half into each saucepan and simmer an additional 5 minutes, or until hot. To get its fun look, pour equal amounts of each soup into each bowl at the same time, and swirl with a knife.