New Orleans Green Gumbo

In 5-quart Dutch oven, cook bacon over medium-low heat until browned. With slotted spoon, remove bacon to paper towels to drain. Reserve bacon for garnish. Discard all but 2 tablespoons bacon fat from Dutch oven. Stir in flour, salt, and ground red pepper and cook over medium heat until golden brown, about 5 minutes, stirring frequently. Stir in chicken broth, fresh greens, spinach, potato, and 4 cups water; heat to boiling over high heat. Reduce heat to low; cover and simmer 20 to 25 minutes until soup thickens slightly and greens are tender, stirring occasionally. Sprinkle bacon over soup to serve.